diff --git a/copperc/src/app/u/datasets/_modals/addattribute.tsx b/copperc/src/app/u/datasets/_modals/addattribute.tsx
index 7e1f1dc7..9dc684ed 100644
--- a/copperc/src/app/u/datasets/_modals/addattribute.tsx
+++ b/copperc/src/app/u/datasets/_modals/addattribute.tsx
@@ -5,7 +5,7 @@ import { useMutation } from "@tanstack/react-query";
 import { edgeclient } from "@/lib/api/client";
 import { components } from "@/lib/api/openapi";
 import { ReactElement, useState } from "react";
-import { DataType, dataTypes, getAttrTypeInfo } from "@/lib/attributes";
+import { AttrDataType, attrDataTypes, getAttrTypeInfo } from "@/lib/attributes";
 
 export function useAddAttributeModal(params: {
 	dataset_id: number;
@@ -20,7 +20,7 @@ export function useAddAttributeModal(params: {
 		response: string | null;
 	}>({ type: null, response: null });
 
-	const [newAttrType, setNewAttrType] = useState<DataType | null>(null);
+	const [newAttrType, setNewAttrType] = useState<AttrDataType | null>(null);
 
 	// Get input ui for attr-specific parameters
 	let NewAttrForm:
@@ -101,7 +101,7 @@ export function useAddAttributeModal(params: {
 				<Select
 					required={true}
 					placeholder={"select attribute type"}
-					data={dataTypes.map((x) => {
+					data={attrDataTypes.map((x) => {
 						const attrdef = getAttrTypeInfo(x);
 						return {
 							label: attrdef.pretty_name,
diff --git a/copperc/src/app/u/items/_panels/controlpanel.tsx b/copperc/src/app/u/items/_panels/controlpanel.tsx
index 0d330e7a..16fb0373 100644
--- a/copperc/src/app/u/items/_panels/controlpanel.tsx
+++ b/copperc/src/app/u/items/_panels/controlpanel.tsx
@@ -16,9 +16,14 @@ export function ControlPanel(params: {
 	// outside of this component, or if `selectedClass` doesn't
 	// initialize as `null`.
 	selectedClass: components["schemas"]["ClassInfo"] | null;
+
 	setSelectedClass: (
 		new_class: components["schemas"]["ClassInfo"] | null,
 	) => void;
+
+	setSelectedDataset: (
+		new_dataset: components["schemas"]["DatasetInfo"] | null,
+	) => void;
 }) {
 	const [selectedDataset, setSelectedDataset] = useState<number | null>(null);
 
@@ -95,64 +100,76 @@ export function ControlPanel(params: {
 	return (
 		<div className={styles.panel} style={{ width: "20rem" }}>
 			<TitleBar text="Control panel" />
-			<div className={styles.panel_content}>
-				<Select
-					label="Select dataset"
-					style={{ width: "100%" }}
-					disabled={datasets.data === undefined}
-					placeholder={
-						datasets.data === undefined ? "Loading..." : "Select a dataset"
-					}
-					data={dataset_data}
-					value={selectedDataset === null ? null : selectedDataset.toString()}
-					onChange={(value) => {
-						const int = value === null ? null : parseInt(value);
-						if (int === selectedDataset) {
-							return;
-						}
-
-						if (int === null || datasets.data === undefined) {
-							setSelectedDataset(null);
-							params.setSelectedClass(null);
-							return;
-						}
 
-						setSelectedDataset(int);
-						params.setSelectedClass(null);
-					}}
-				/>
-
-				<Select
-					label="Select class"
-					style={{ width: "100%" }}
-					disabled={datasets.data === undefined}
-					placeholder={
-						datasets.data === undefined ? "Loading..." : "Select a class"
-					}
-					data={class_data}
-					value={
-						params.selectedClass === null
-							? null
-							: params.selectedClass.id.toString()
-					}
-					onChange={(value) => {
-						const int = value === null ? null : parseInt(value);
-						if (int === params.selectedClass) {
-							return;
+			<div
+				style={{
+					overflowY: "scroll",
+					marginTop: "1rem",
+				}}
+			>
+				{/* TODO: clean up, `style` shouldn't be necessary here */}
+				<div className={styles.panel_content} style={{ padding: 0 }}>
+					<Select
+						label="Select dataset"
+						style={{ width: "100%" }}
+						disabled={datasets.data === undefined}
+						placeholder={
+							datasets.data === undefined ? "Loading..." : "Select a dataset"
 						}
-
-						if (int === null || datasets.data === undefined) {
+						data={dataset_data}
+						value={selectedDataset === null ? null : selectedDataset.toString()}
+						onChange={(value) => {
+							const int = value === null ? null : parseInt(value);
+							if (int === selectedDataset) {
+								return;
+							}
+
+							if (int === null || datasets.data === undefined) {
+								setSelectedDataset(null);
+								params.setSelectedClass(null);
+								params.setSelectedDataset(null);
+								return;
+							}
+
+							setSelectedDataset(int);
 							params.setSelectedClass(null);
-							return;
+							params.setSelectedDataset(null);
+						}}
+					/>
+
+					<Select
+						label="Select class"
+						style={{ width: "100%" }}
+						disabled={datasets.data === undefined}
+						placeholder={
+							datasets.data === undefined ? "Loading..." : "Select a class"
 						}
-
-						const c = datasets.data
-							.find((x) => x.id === selectedDataset)!
-							.classes.find((x) => x.id === int)!;
-
-						params.setSelectedClass(c);
-					}}
-				/>
+						data={class_data}
+						value={
+							params.selectedClass === null
+								? null
+								: params.selectedClass.id.toString()
+						}
+						onChange={(value) => {
+							const int = value === null ? null : parseInt(value);
+							if (int === params.selectedClass) {
+								return;
+							}
+
+							if (int === null || datasets.data === undefined) {
+								params.setSelectedClass(null);
+								params.setSelectedDataset(null);
+								return;
+							}
+
+							const d = datasets.data.find((x) => x.id === selectedDataset)!;
+							const c = d.classes.find((x) => x.id === int)!;
+
+							params.setSelectedClass(c);
+							params.setSelectedDataset(d);
+						}}
+					/>
+				</div>
 			</div>
 		</div>
 	);
diff --git a/copperc/src/app/u/items/_panels/edit.module.scss b/copperc/src/app/u/items/_panels/edit.module.scss
index baced154..3043e9cf 100644
--- a/copperc/src/app/u/items/_panels/edit.module.scss
+++ b/copperc/src/app/u/items/_panels/edit.module.scss
@@ -2,32 +2,42 @@
 	display: flex;
 	flex-direction: row;
 	align-items: first baseline;
+	align-items: stretch;
 	justify-self: start;
-	gap: 4rem;
+	justify-content: space-between;
+	gap: 2rem;
 
 	width: 100%;
 	height: 100%;
+	padding-bottom: 2rem;
 }
 
-.attr_container {
-	display: flex;
-	flex-direction: column;
+.attr_container_scroll {
 	flex-grow: 1;
+	max-width: 80rem;
 
 	max-height: 100%;
-	overflow: scroll;
+	overflow-y: scroll;
+	padding-left: 0.5rem;
+	padding-right: 1rem;
+	padding-top: 0.5rem;
+	padding-bottom: 2rem;
+}
+
+.attr_container {
+	display: flex;
+	flex-direction: column;
 
 	.attr_row {
 		display: flex;
 		flex-direction: row;
 		overflow: hidden;
 		background-color: var(--mantine-color-dark-9);
-		min-height: 3rem;
+		min-height: min-content;
 		max-height: 10rem;
 
 		.row_icon {
 			width: 2rem;
-			min-height: 100%;
 			background-color: var(--mantine-primary-color-8);
 			display: flex;
 			align-items: center;
@@ -41,7 +51,6 @@
 			justify-content: center;
 
 			width: 10rem;
-			min-height: 100%;
 			padding: 0.25rem;
 			background-color: var(--mantine-color-dark-8);
 			user-select: none;
@@ -67,7 +76,12 @@
 		.row_value_new {
 			display: flex;
 			flex-direction: column;
-			justify-content: center;
+
+			// hmm, justify-content is weird.
+			// we have it in value_old but not here
+			// because this column is usually taller.
+			//
+			// That's a hack, though.
 
 			padding: 0.25rem;
 			overflow-x: scroll;
@@ -84,7 +98,10 @@
 	vertical-align: top;
 	flex-direction: column;
 
-	width: 30%;
+	// min-width so that `attr_container` doesn't steal
+	// width from the panel. Could also set `flex-shrink: 0`.
+	min-width: 30%;
+
 	height: 100%;
 
 	border-style: solid;
diff --git a/copperc/src/app/u/items/_panels/editpanel.tsx b/copperc/src/app/u/items/_panels/editpanel.tsx
index 9ccf21c1..dd0e035d 100644
--- a/copperc/src/app/u/items/_panels/editpanel.tsx
+++ b/copperc/src/app/u/items/_panels/editpanel.tsx
@@ -6,14 +6,7 @@ import stylesEdit from "./edit.module.scss";
 import { components } from "@/lib/api/openapi";
 import { X } from "lucide-react";
 import { getAttrTypeInfo } from "@/lib/attributes";
-import {
-	Fragment,
-	ReactNode,
-	useCallback,
-	useEffect,
-	useMemo,
-	useState,
-} from "react";
+import { ReactNode, useCallback, useEffect, useMemo, useState } from "react";
 import { Button, Text } from "@mantine/core";
 import { Wrapper } from "@/components/spinner";
 
@@ -167,136 +160,138 @@ function AttrList(params: {
 	return (
 		<div
 			key={`attrlist-${params.selectedItems.map((x) => x.id).join(",")}`}
-			className={stylesEdit.attr_container}
+			className={stylesEdit.attr_container_scroll}
 		>
-			{params.class.attributes.map((attr) => {
-				const shared =
-					params.sharedAttributes.find((x) => x.id === attr.id) !== undefined;
+			<div className={stylesEdit.attr_container}>
+				{params.class.attributes.map((attr) => {
+					const shared =
+						params.sharedAttributes.find((x) => x.id === attr.id) !== undefined;
 
-				const attrdef = getAttrTypeInfo(attr.data_type.type);
+					const attrdef = getAttrTypeInfo(attr.data_type.type);
 
-				if (shared) {
-					const value =
-						params.selectedItems[0]!.attribute_values[attr.id] || null;
+					if (shared) {
+						const value =
+							params.selectedItems[0]!.attribute_values[attr.id] || null;
 
-					if (!(value === null || value.type === attr.data_type.type)) {
-						throw new Error("Attribute type mismatch");
-					}
+						if (!(value === null || value.type === attr.data_type.type)) {
+							throw new Error("Attribute type mismatch");
+						}
 
-					return (
-						<div key={`attr-row-${attr.id}`} className={stylesEdit.attr_row}>
-							<div className={stylesEdit.row_icon}>{attrdef.icon}</div>
-							<div className={stylesEdit.row_name}>{attr.name}</div>
-							<div className={stylesEdit.row_value_old}>
-								{attrdef.editor.type === "panel" ? (
-									params.attr?.id === attr.id ? (
+						return (
+							<div key={`attr-row-${attr.id}`} className={stylesEdit.attr_row}>
+								<div className={stylesEdit.row_icon}>{attrdef.icon}</div>
+								<div className={stylesEdit.row_name}>{attr.name}</div>
+								<div className={stylesEdit.row_value_old}>
+									{attrdef.editor.type === "panel" ? (
+										params.attr?.id === attr.id ? (
+											<Button fullWidth disabled>
+												Viewing in panel
+											</Button>
+										) : (
+											<Button
+												fullWidth
+												onClick={() => {
+													params.setPanelAttr(attr.id);
+												}}
+											>
+												View in panel
+											</Button>
+										)
+									) : value === null ? (
+										<div
+											style={{
+												paddingLeft: "0.5rem",
+												width: "100%",
+												overflow: "hidden",
+												textOverflow: "ellipsis",
+												whiteSpace: "nowrap",
+												color: "var(--mantine-color-dimmed)",
+												fontStyle: "italic",
+											}}
+										>
+											Unset
+										</div>
+									) : (
+										attrdef.editor.old_value(value)
+									)}
+								</div>
+								<div className={stylesEdit.row_value_new}>
+									{attrdef.editor.type === "panel" ? (
+										params.attr?.id === attr.id ? (
+											<Button fullWidth disabled>
+												Viewing in panel
+											</Button>
+										) : (
+											<Button
+												fullWidth
+												onClick={() => {
+													params.setPanelAttr(attr.id);
+												}}
+											>
+												View in panel
+											</Button>
+										)
+									) : (
+										attrdef.editor.new_value({
+											value,
+											onChange: console.log,
+										})
+									)}
+								</div>
+							</div>
+						);
+					} else {
+						return (
+							<div key={`attr-row-${attr.id}`} className={stylesEdit.attr_row}>
+								<div className={stylesEdit.row_icon}>{attrdef.icon}</div>
+								<div className={stylesEdit.row_name}>{attr.name}</div>
+								<div className={stylesEdit.row_value_old}>
+									{attrdef.editor.type === "panel" ? (
 										<Button fullWidth disabled>
-											Viewing in panel
+											Differs
 										</Button>
 									) : (
-										<Button
-											fullWidth
-											onClick={() => {
-												params.setPanelAttr(attr.id);
+										<div
+											style={{
+												paddingLeft: "0.5rem",
+												width: "100%",
+												overflow: "hidden",
+												textOverflow: "ellipsis",
+												whiteSpace: "nowrap",
+												color: "var(--mantine-color-dimmed)",
+												fontStyle: "italic",
 											}}
 										>
-											View in panel
-										</Button>
-									)
-								) : value === null ? (
-									<div
-										style={{
-											paddingLeft: "0.5rem",
-											width: "100%",
-											overflow: "hidden",
-											textOverflow: "ellipsis",
-											whiteSpace: "nowrap",
-											color: "var(--mantine-color-dimmed)",
-											fontStyle: "italic",
-										}}
-									>
-										Unset
-									</div>
-								) : (
-									attrdef.editor.old_value(value)
-								)}
-							</div>
-							<div className={stylesEdit.row_value_new}>
-								{attrdef.editor.type === "panel" ? (
-									params.attr?.id === attr.id ? (
+											Differs
+										</div>
+									)}
+								</div>
+								<div className={stylesEdit.row_value_new}>
+									{attrdef.editor.type === "panel" ? (
 										<Button fullWidth disabled>
-											Viewing in panel
+											Differs
 										</Button>
 									) : (
-										<Button
-											fullWidth
-											onClick={() => {
-												params.setPanelAttr(attr.id);
+										<div
+											style={{
+												paddingLeft: "0.5rem",
+												width: "100%",
+												overflow: "hidden",
+												textOverflow: "ellipsis",
+												whiteSpace: "nowrap",
+												color: "var(--mantine-color-dimmed)",
+												fontStyle: "italic",
 											}}
 										>
-											View in panel
-										</Button>
-									)
-								) : (
-									attrdef.editor.new_value({
-										value,
-										onChange: console.log,
-									})
-								)}
-							</div>
-						</div>
-					);
-				} else {
-					return (
-						<div key={`attr-row-${attr.id}`} className={stylesEdit.attr_row}>
-							<div className={stylesEdit.row_icon}>{attrdef.icon}</div>
-							<div className={stylesEdit.row_name}>{attr.name}</div>
-							<div className={stylesEdit.row_value_old}>
-								{attrdef.editor.type === "panel" ? (
-									<Button fullWidth disabled>
-										Differs
-									</Button>
-								) : (
-									<div
-										style={{
-											paddingLeft: "0.5rem",
-											width: "100%",
-											overflow: "hidden",
-											textOverflow: "ellipsis",
-											whiteSpace: "nowrap",
-											color: "var(--mantine-color-dimmed)",
-											fontStyle: "italic",
-										}}
-									>
-										Differs
-									</div>
-								)}
-							</div>
-							<div className={stylesEdit.row_value_new}>
-								{attrdef.editor.type === "panel" ? (
-									<Button fullWidth disabled>
-										Differs
-									</Button>
-								) : (
-									<div
-										style={{
-											paddingLeft: "0.5rem",
-											width: "100%",
-											overflow: "hidden",
-											textOverflow: "ellipsis",
-											whiteSpace: "nowrap",
-											color: "var(--mantine-color-dimmed)",
-											fontStyle: "italic",
-										}}
-									>
-										Differs
-									</div>
-								)}
+											Differs
+										</div>
+									)}
+								</div>
 							</div>
-						</div>
-					);
-				}
-			})}
+						);
+					}
+				})}
+			</div>
 		</div>
 	);
 }
@@ -352,16 +347,15 @@ function Panel(params: {
 
 	// Key here is important, it makes sure we get a new panel each time we select an item
 	return (
-		<Fragment
+		<div
 			key={`panel-${params.attr?.id}-${params.selectedItems.map((x) => x.id).join(",")}`}
+			className={stylesEdit.panel_container}
 		>
-			<div className={stylesEdit.panel_container}>
-				<div className={stylesEdit.panel_title}>
-					<div className={stylesEdit.panel_title_icon}>{icon}</div>
-					<div className={stylesEdit.panel_title_name}>{title}</div>
-				</div>
-				<div className={stylesEdit.panel_body}>{body}</div>
+			<div className={stylesEdit.panel_title}>
+				<div className={stylesEdit.panel_title_icon}>{icon}</div>
+				<div className={stylesEdit.panel_title_name}>{title}</div>
 			</div>
-		</Fragment>
+			<div className={stylesEdit.panel_body}>{body}</div>
+		</div>
 	);
 }
diff --git a/copperc/src/app/u/items/_panels/itemtable.tsx b/copperc/src/app/u/items/_panels/itemtable.tsx
index 7d1ce35a..fa758d33 100644
--- a/copperc/src/app/u/items/_panels/itemtable.tsx
+++ b/copperc/src/app/u/items/_panels/itemtable.tsx
@@ -34,6 +34,7 @@ const fetchSize = 50;
  * Generate a react-table column for the given attribute
  */
 function gen_attr_col(
+	dataset: components["schemas"]["DatasetInfo"],
 	attr: components["schemas"]["AttributeInfo"],
 ): ColumnDef<components["schemas"]["ItemlistItemInfo"]> {
 	return {
@@ -80,7 +81,7 @@ function gen_attr_col(
 					</div>
 				);
 			} else {
-				jsx = attrdef.table_cell(value);
+				jsx = attrdef.table_cell({ value, dataset });
 			}
 
 			if (jsx === null) {
@@ -93,7 +94,10 @@ function gen_attr_col(
 	};
 }
 
-function initialize_columns(item_class: components["schemas"]["ClassInfo"]) {
+function initialize_columns(
+	dataset: components["schemas"]["DatasetInfo"],
+	item_class: components["schemas"]["ClassInfo"],
+) {
 	const init: ColumnDef<components["schemas"]["ItemlistItemInfo"]>[] = [
 		// Selection column
 		{
@@ -183,7 +187,7 @@ function initialize_columns(item_class: components["schemas"]["ClassInfo"]) {
 		if (max_cols === 0) break;
 		max_cols -= 1;
 
-		init.push(gen_attr_col(attr));
+		init.push(gen_attr_col(dataset, attr));
 	}
 
 	return init;
@@ -227,6 +231,7 @@ function useItemQuery(item_class: components["schemas"]["ClassInfo"] | null) {
 }
 
 function TableHeader(params: {
+	dataset: components["schemas"]["DatasetInfo"];
 	item_class: components["schemas"]["ClassInfo"];
 
 	header: Header<
@@ -263,6 +268,15 @@ function TableHeader(params: {
 	const [selectedAttr, setSelectedAttr] = useState<number | null>(null);
 	const [opened, setOpened] = useState(false);
 
+	const available_attrs = params.item_class.attributes
+		.map((a) => ({
+			label: a.name,
+			value: a.id.toString(),
+			disabled:
+				params.columns.find((c) => c.id === `attr-${a.id}`) !== undefined,
+		}))
+		.filter((v) => !v.disabled);
+
 	return (
 		<div
 			className={tableStyle.th}
@@ -282,6 +296,8 @@ function TableHeader(params: {
 						flexGrow: 1,
 						overflow: "hidden",
 						textOverflow: "ellipsis",
+						textWrap: "nowrap",
+						whiteSpace: "nowrap",
 					}}
 				>
 					{params.header.isPlaceholder
@@ -328,7 +344,12 @@ function TableHeader(params: {
 									<Select
 										comboboxProps={{ withinPortal: false }}
 										style={{ width: "100%" }}
-										placeholder={"Select an attribute"}
+										placeholder={
+											available_attrs.length === 0
+												? "No more attributes"
+												: "Select an attribute"
+										}
+										disabled={available_attrs.length === 0}
 										value={selectedAttr?.toString()}
 										onChange={(value) => {
 											if (value === null) {
@@ -342,21 +363,15 @@ function TableHeader(params: {
 												setSelectedAttr(null);
 											}
 										}}
-										data={params.item_class.attributes
-											.map((a) => ({
-												label: a.name,
-												value: a.id.toString(),
-												disabled:
-													params.columns.find(
-														(c) => c.id === `attr-${a.id}`,
-													) !== undefined,
-											}))
-											.filter((v) => !v.disabled)}
+										data={available_attrs}
 									/>
 									<Button
 										style={{ marginTop: "0.5rem" }}
 										size="xs"
 										fullWidth
+										disabled={
+											available_attrs.length === 0 || selectedAttr === null
+										}
 										onClick={() => {
 											const attr = params.item_class.attributes.find(
 												(a) => a.id === selectedAttr,
@@ -365,14 +380,16 @@ function TableHeader(params: {
 											if (attr !== undefined) {
 												params.setColumns((cols) => [
 													...cols,
-													gen_attr_col(attr),
+													gen_attr_col(params.dataset, attr),
 												]);
 											}
 
 											setOpened(false);
 										}}
 									>
-										Add column
+										{available_attrs.length === 0
+											? "All attributes shown"
+											: "Add attribute"}
 									</Button>
 
 									<Button
@@ -431,6 +448,7 @@ function TableHeader(params: {
 }
 
 export function ItemTablePanel(params: {
+	dataset: components["schemas"]["DatasetInfo"] | null;
 	class: components["schemas"]["ClassInfo"] | null;
 	setSelectedItems: (
 		items: components["schemas"]["ItemlistItemInfo"][],
@@ -458,12 +476,28 @@ export function ItemTablePanel(params: {
 		let total = 0;
 		if (items.data !== undefined && items.data.pages.length !== 0) {
 			const last = items.data.pages[items.data.pages.length - 1]!;
-			total = (last as Exclude<typeof last, never[]>).total;
+			if (!Array.isArray(last)) {
+				total = (last as Exclude<typeof last, never[]>).total;
+			}
 		}
 
 		return total;
 	}, [items.data]);
 
+	const lastWasZero = useMemo(() => {
+		let last_was_zero = false;
+
+		if (items.data !== undefined && items.data.pages.length !== 0) {
+			const last = items.data.pages[items.data.pages.length - 1]!;
+			if (!Array.isArray(last)) {
+				last_was_zero =
+					(last as Exclude<typeof last, never[]>).items.length === 0;
+			}
+		}
+
+		return last_was_zero;
+	}, [items.data]);
+
 	// Called on scroll and on mount to fetch data
 	// as the user scrolls down
 	const totalFetched = flatData.length;
@@ -476,13 +510,14 @@ export function ItemTablePanel(params: {
 				if (
 					scrollHeight - scrollTop - clientHeight < 500 &&
 					!items.isFetching &&
-					totalFetched < totalItems
+					totalFetched < totalItems &&
+					!lastWasZero
 				) {
 					items.fetchNextPage();
 				}
 			}
 		},
-		[items, totalFetched, totalItems],
+		[items, totalFetched, totalItems, lastWasZero],
 	);
 
 	// check if our table is already scrolled to the bottom,
@@ -492,7 +527,9 @@ export function ItemTablePanel(params: {
 	}, [fetchMoreOnBottomReached]);
 
 	const [columns, setColumns] = useState(
-		params.class === null ? [] : initialize_columns(params.class),
+		params.class === null || params.dataset === null
+			? []
+			: initialize_columns(params.dataset, params.class),
 	);
 
 	const table = useReactTable({
@@ -523,7 +560,11 @@ export function ItemTablePanel(params: {
 				</Wrapper>
 			</div>
 		</div>;
-	} else if (flatData === undefined || params.class === null) {
+	} else if (
+		flatData === undefined ||
+		params.class === null ||
+		params.dataset === null
+	) {
 		return (
 			<div className={mainStyle.panel}>
 				<TitleBar text="Items" />
@@ -552,6 +593,7 @@ export function ItemTablePanel(params: {
 					<div key={headerGroup.id} className={tableStyle.tr}>
 						{headerGroup.headers.map((header) => (
 							<TableHeader
+								dataset={params.dataset!}
 								key={header.id}
 								item_class={params.class!}
 								header={header}
@@ -596,7 +638,7 @@ export function ItemTablePanel(params: {
 						))}
 					</div>
 				))}
-				{totalFetched >= totalItems ? null : (
+				{totalFetched >= totalItems || lastWasZero ? null : (
 					<div
 						style={{
 							display: "flex",
diff --git a/copperc/src/app/u/items/items.module.scss b/copperc/src/app/u/items/items.module.scss
index 4dc88510..e655ee7f 100644
--- a/copperc/src/app/u/items/items.module.scss
+++ b/copperc/src/app/u/items/items.module.scss
@@ -1,19 +1,21 @@
 .main_top {
 	display: flex;
 	flex-direction: row;
-	height: calc(100% - 30rem);
+	height: 55%;
 	max-width: 100%;
-	gap: 3rem;
+	gap: 2rem;
 
 	padding: 2rem;
+	padding-bottom: 1rem;
 	overflow: hidden;
 }
 
 .main_bottom {
-	height: 30rem;
+	height: 45%;
 	max-width: 100%;
 
 	padding: 2rem;
+	padding-top: 1rem;
 	overflow: hidden;
 }
 
diff --git a/copperc/src/app/u/items/page.tsx b/copperc/src/app/u/items/page.tsx
index 299a5926..4e56f2f9 100644
--- a/copperc/src/app/u/items/page.tsx
+++ b/copperc/src/app/u/items/page.tsx
@@ -13,6 +13,10 @@ export default function Page() {
 		components["schemas"]["ItemlistItemInfo"][]
 	>([]);
 
+	const [selectedDataset, setSelectedDataset] = useState<
+		components["schemas"]["DatasetInfo"] | null
+	>(null);
+
 	const [selectedClass, setSelectedClass] = useState<
 		components["schemas"]["ClassInfo"] | null
 	>(null);
@@ -23,6 +27,7 @@ export default function Page() {
 				<ControlPanel
 					selectedClass={selectedClass}
 					setSelectedClass={setSelectedClass}
+					setSelectedDataset={setSelectedDataset}
 				/>
 
 				<ItemTablePanel
@@ -30,6 +35,7 @@ export default function Page() {
 					// when we select a new class
 					key={`${selectedClass?.id}`}
 					class={selectedClass}
+					dataset={selectedDataset}
 					setSelectedItems={setSelectedItems}
 				/>
 			</div>
diff --git a/copperc/src/app/u/pipeline/_nodes/additem.tsx b/copperc/src/app/u/pipeline/_nodes/additem.tsx
index 50f8e7a7..777a5d2a 100644
--- a/copperc/src/app/u/pipeline/_nodes/additem.tsx
+++ b/copperc/src/app/u/pipeline/_nodes/additem.tsx
@@ -1,4 +1,4 @@
-import { Select } from "@mantine/core";
+import { Select, Switch } from "@mantine/core";
 import {
 	Node,
 	NodeProps,
@@ -8,17 +8,17 @@ import {
 import { BaseNode } from "./base";
 import { useQuery } from "@tanstack/react-query";
 import { edgeclient } from "@/lib/api/client";
-import { NodeDef } from ".";
+import { NodeDef, PipelineDataType } from ".";
 import { useCallback } from "react";
-import { DataType } from "@/lib/attributes";
 
 type AddItemNodeType = Node<
 	{
 		dataset: null | number;
 		class: null | number;
+		on_unique_violation: "fail" | "select";
 
 		inputs: {
-			type: DataType;
+			type: PipelineDataType;
 			id: string;
 			tooltip: string;
 		}[];
@@ -72,7 +72,10 @@ function AddItemNodeElement({ data, id }: NodeProps<AddItemNodeType>) {
 								?.classes.find((x) => x.id === cls)
 								?.attributes.map((x) => ({
 									id: x.name,
-									type: x.data_type.type,
+									type:
+										x.data_type.type === "Reference"
+											? `Reference(${x.data_type.class})`
+											: x.data_type.type,
 									tooltip: x.name,
 								})) || undefined,
 			});
@@ -82,7 +85,22 @@ function AddItemNodeElement({ data, id }: NodeProps<AddItemNodeType>) {
 
 	return (
 		<>
-			<BaseNode id={id} title={"Add Item"} inputs={data.inputs}>
+			<BaseNode
+				id={id}
+				title={"Add Item"}
+				inputs={data.inputs}
+				outputs={
+					data.class === null
+						? []
+						: [
+								{
+									id: "new_item",
+									tooltip: "Reference to new item",
+									type: `Reference(${data.class})`,
+								},
+							]
+				}
+			>
 				<Select
 					clearable
 					label="Select dataset"
@@ -152,6 +170,17 @@ function AddItemNodeElement({ data, id }: NodeProps<AddItemNodeType>) {
 					}}
 					value={data.class?.toString() || null}
 				/>
+
+				<Switch
+					label="Select if not unique"
+					checked={data.on_unique_violation === "select"}
+					onChange={(e) => {
+						data.on_unique_violation = e.currentTarget.checked
+							? "select"
+							: "fail";
+						updateNodeInternals(id);
+					}}
+				/>
 			</BaseNode>
 		</>
 	);
@@ -165,11 +194,22 @@ export const AddItemNode: NodeDef<AddItemNodeType> = {
 	initialData: {
 		dataset: null,
 		class: null,
+		on_unique_violation: "fail",
 		inputs: [],
 	},
 
-	getInputs: (data) => data.inputs,
-	getOutputs: () => [],
+	getInputs: (data) =>
+		data.inputs.map((x) => {
+			return {
+				id: x.id,
+				type: x.type,
+			};
+		}),
+
+	getOutputs: (data) =>
+		data.class === null
+			? []
+			: [{ id: "new_item", type: `Reference(${data.class})` }],
 
 	serialize: (node) => {
 		if (node.data.class === null || node.data.dataset === null) {
@@ -177,6 +217,11 @@ export const AddItemNode: NodeDef<AddItemNodeType> = {
 		}
 
 		return {
+			// TODO: add ui
+			on_unique_violation: {
+				parameter_type: "String",
+				value: node.data.on_unique_violation,
+			},
 			dataset: {
 				parameter_type: "Integer",
 				value: node.data.dataset,
@@ -213,15 +258,28 @@ export const AddItemNode: NodeDef<AddItemNodeType> = {
 		const clsinfo =
 			datasetinfo?.classes.find((x) => x.id === cls.value) || null;
 
+		const ouv = serialized.params.on_unique_violation;
+		if (
+			ouv?.parameter_type !== "String" ||
+			!(ouv?.value === "fail" || ouv?.value === "select")
+		) {
+			return null;
+		}
+
 		return {
 			dataset: datasetinfo?.id || null,
 			class: clsinfo?.id || null,
+			on_unique_violation: ouv.value as "fail" | "select",
 
 			inputs:
 				clsinfo?.attributes.map((x) => ({
 					id: x.name,
-					type: x.data_type.type,
 					tooltip: x.name,
+
+					type:
+						x.data_type.type === "Reference"
+							? `Reference(${x.data_type.class})`
+							: x.data_type.type,
 				})) || [],
 		};
 	},
diff --git a/copperc/src/app/u/pipeline/_nodes/base.tsx b/copperc/src/app/u/pipeline/_nodes/base.tsx
index 6f5f3bce..7555e8b4 100644
--- a/copperc/src/app/u/pipeline/_nodes/base.tsx
+++ b/copperc/src/app/u/pipeline/_nodes/base.tsx
@@ -3,7 +3,8 @@ import { Handle, Node, Position, useReactFlow } from "@xyflow/react";
 import style from "./nodes.module.scss";
 import { ActionIcon } from "@mantine/core";
 import { Trash2 } from "lucide-react";
-import { DataType, getAttrTypeInfo } from "@/lib/attributes";
+import { PipelineDataType } from ".";
+import { AttrDataType, getAttrTypeInfo } from "@/lib/attributes";
 
 function EmptyMarker() {
 	return (
@@ -27,13 +28,13 @@ export function BaseNode(params: {
 	top_color?: string;
 
 	outputs?: {
-		type: DataType;
+		type: PipelineDataType;
 		id: string;
 		tooltip: string;
 	}[];
 
 	inputs?: {
-		type: DataType;
+		type: PipelineDataType;
 		id: string;
 		tooltip: string;
 	}[];
@@ -77,7 +78,12 @@ export function BaseNode(params: {
 										key={`handle-${x.id}`}
 										className={`${style.node_port} ${style.input}`}
 									>
-										{getAttrTypeInfo(x.type).icon}
+										{
+											// Convert `Reference(number)` into `number
+											x.type.startsWith("Reference")
+												? getAttrTypeInfo("Reference").icon
+												: getAttrTypeInfo(x.type as AttrDataType).icon
+										}
 										<Handle type="target" position={Position.Left} id={x.id} />
 										<div className={`${style.port_tooltip} ${style.input}`}>
 											{x.tooltip}
@@ -103,7 +109,12 @@ export function BaseNode(params: {
 										key={`handle-${x.id}`}
 										className={`${style.node_port} ${style.output}`}
 									>
-										{getAttrTypeInfo(x.type).icon}
+										{
+											// Convert `Reference(number)` into `number
+											x.type.startsWith("Reference")
+												? getAttrTypeInfo("Reference").icon
+												: getAttrTypeInfo(x.type as AttrDataType).icon
+										}
 										<Handle type="source" position={Position.Right} id={x.id} />
 										<div className={`${style.port_tooltip} ${style.output}`}>
 											{x.tooltip}
diff --git a/copperc/src/app/u/pipeline/_nodes/constant.tsx b/copperc/src/app/u/pipeline/_nodes/constant.tsx
index 0f806133..f094e13c 100644
--- a/copperc/src/app/u/pipeline/_nodes/constant.tsx
+++ b/copperc/src/app/u/pipeline/_nodes/constant.tsx
@@ -2,8 +2,8 @@ import { NumberInput, Select, TextInput } from "@mantine/core";
 import { Node, NodeProps, useReactFlow } from "@xyflow/react";
 import { BaseNode } from "./base";
 import { NodeDef } from ".";
+import { stringUnionToArray } from "@/lib/util";
 
-const types = ["Text", "Integer", "Float"] as const;
 type ValueType =
 	| {
 			type: "Text";
@@ -12,8 +12,25 @@ type ValueType =
 	| {
 			type: "Integer";
 			value: number;
+	  }
+	| {
+			type: "Float";
+			value: number;
+	  }
+	| {
+			type: "Boolean";
+			value: boolean;
 	  };
 
+type ConstType = ValueType["type"];
+
+export const constTypes = stringUnionToArray<ConstType>()(
+	"Text",
+	"Integer",
+	"Float",
+	"Boolean",
+);
+
 type ConstantNodeType = Node<
 	{
 		value: ValueType;
@@ -45,9 +62,9 @@ function ConstantNodeElement({ data, id }: NodeProps<ConstantNodeType>) {
 		input = (
 			<NumberInput
 				label="Value"
-				placeholder="enter constant number"
+				placeholder="enter constant integer"
 				onChange={(value) => {
-					if (typeof value === "string") {
+					if (typeof value !== "number") {
 						return;
 					}
 
@@ -62,6 +79,44 @@ function ConstantNodeElement({ data, id }: NodeProps<ConstantNodeType>) {
 				allowDecimal={false}
 			/>
 		);
+	} else if (data.value.type === "Float") {
+		input = (
+			<NumberInput
+				label="Value"
+				placeholder="enter constant float"
+				onChange={(value) => {
+					if (typeof value !== "number") {
+						return;
+					}
+
+					updateNodeData(id, {
+						value: {
+							type: "Float",
+							value,
+						},
+					});
+				}}
+				value={data.value.value}
+				allowDecimal={true}
+			/>
+		);
+	} else if (data.value.type === "Boolean") {
+		input = (
+			<Select
+				label="Value"
+				placeholder="enter constant boolean"
+				data={["true", "false"]}
+				value={data.value.value ? "true" : "false"}
+				onChange={(value) => {
+					updateNodeData(id, {
+						value: {
+							type: "Boolean",
+							value: value === "true",
+						},
+					});
+				}}
+			/>
+		);
 	}
 
 	return (
@@ -76,8 +131,10 @@ function ConstantNodeElement({ data, id }: NodeProps<ConstantNodeType>) {
 				<Select
 					label="Data type"
 					placeholder="Pick value"
-					data={types}
-					onChange={(value) => {
+					data={constTypes}
+					onChange={(v) => {
+						const value = v as ConstType | null;
+
 						if (value === null || value == data.value.type) {
 							return;
 						}
@@ -102,6 +159,20 @@ function ConstantNodeElement({ data, id }: NodeProps<ConstantNodeType>) {
 									value: 0,
 								},
 							});
+						} else if (value === "Float") {
+							updateNodeData(id, {
+								value: {
+									type: "Float",
+									value: 0,
+								},
+							});
+						} else if (value === "Boolean") {
+							updateNodeData(id, {
+								value: {
+									type: "Boolean",
+									value: false,
+								},
+							});
 						}
 					}}
 					value={data.value.type}
diff --git a/copperc/src/app/u/pipeline/_nodes/extractcovers.tsx b/copperc/src/app/u/pipeline/_nodes/extractcovers.tsx
index bef13427..c7691aed 100644
--- a/copperc/src/app/u/pipeline/_nodes/extractcovers.tsx
+++ b/copperc/src/app/u/pipeline/_nodes/extractcovers.tsx
@@ -11,7 +11,7 @@ function ExtractCoversNodeElement({ id }: NodeProps<ExtractCoversNodeType>) {
 				id={id}
 				title={"Extract covers"}
 				inputs={[{ id: "data", type: "Blob", tooltip: "Audio data" }]}
-				outputs={[{ id: "out", type: "Blob", tooltip: "Cover" }]}
+				outputs={[{ id: "cover_data", type: "Blob", tooltip: "Cover" }]}
 			/>
 		</>
 	);
@@ -23,7 +23,7 @@ export const ExtractCoversNode: NodeDef<ExtractCoversNodeType> = {
 	node: ExtractCoversNodeElement,
 
 	getInputs: () => [{ id: "data", type: "Blob" }],
-	getOutputs: () => [{ id: "out", type: "Blob" }],
+	getOutputs: () => [{ id: "cover_data", type: "Blob" }],
 
 	initialData: {},
 	serialize: () => ({}),
diff --git a/copperc/src/app/u/pipeline/_nodes/ifnone.tsx b/copperc/src/app/u/pipeline/_nodes/ifnone.tsx
index ecf95e57..2eaaddb6 100644
--- a/copperc/src/app/u/pipeline/_nodes/ifnone.tsx
+++ b/copperc/src/app/u/pipeline/_nodes/ifnone.tsx
@@ -1,13 +1,12 @@
-import { NodeDef } from ".";
+import { NodeDef, PipelineDataType } from ".";
 import { BaseNode } from "./base";
 import { Node, NodeProps, useReactFlow } from "@xyflow/react";
 import { Select } from "@mantine/core";
-import { components } from "@/lib/api/openapi";
-import { DataType, dataTypes } from "@/lib/attributes";
+import { attrDataTypes } from "@/lib/attributes";
 
 type IfNoneNodeType = Node<
 	{
-		type: DataType;
+		type: PipelineDataType;
 	},
 	"ifnone"
 >;
@@ -30,7 +29,7 @@ function IfNoneNodeElement({ data, id }: NodeProps<IfNoneNodeType>) {
 					clearable={false}
 					label="Data type"
 					placeholder="Pick value"
-					data={dataTypes}
+					data={attrDataTypes}
 					onChange={(value) => {
 						if (value === null || value === data.type) {
 							return;
@@ -80,7 +79,7 @@ export const IfNoneNode: NodeDef<IfNoneNodeType> = {
 		}
 
 		return {
-			type: t.value as components["schemas"]["AttrDataStub"]["type"],
+			type: t.value as PipelineDataType,
 		};
 	},
 };
diff --git a/copperc/src/app/u/pipeline/_nodes/index.tsx b/copperc/src/app/u/pipeline/_nodes/index.tsx
index ce70b216..c24cc996 100644
--- a/copperc/src/app/u/pipeline/_nodes/index.tsx
+++ b/copperc/src/app/u/pipeline/_nodes/index.tsx
@@ -8,7 +8,12 @@ import { IfNoneNode } from "./ifnone";
 import { InputNode } from "./input";
 import { StripTagsNode } from "./striptags";
 import { Node, NodeProps, NodeTypes } from "@xyflow/react";
-import { DataType } from "@/lib/attributes";
+import { AttrDataType } from "@/lib/attributes";
+
+// Corresponds to `PipeData` in our Rust code
+export type PipelineDataType =
+	| Exclude<AttrDataType, "Reference">
+	| `Reference(${number})`;
 
 export type NodeDef<NodeType extends Node> = {
 	xyflow_node_type: string;
@@ -21,12 +26,12 @@ export type NodeDef<NodeType extends Node> = {
 
 	getInputs: (data: NodeType["data"]) => {
 		id: string;
-		type: DataType;
+		type: PipelineDataType;
 	}[];
 
 	getOutputs: (data: NodeType["data"]) => {
 		id: string;
-		type: DataType;
+		type: PipelineDataType;
 	}[];
 
 	/**
diff --git a/copperc/src/app/u/pipeline/_nodes/input.tsx b/copperc/src/app/u/pipeline/_nodes/input.tsx
index b0d836b2..f1cb207f 100644
--- a/copperc/src/app/u/pipeline/_nodes/input.tsx
+++ b/copperc/src/app/u/pipeline/_nodes/input.tsx
@@ -1,19 +1,29 @@
 import { Select } from "@mantine/core";
 import { Node, NodeProps, useReactFlow } from "@xyflow/react";
 import { BaseNode } from "./base";
-import { dataTypes } from "@/lib/attributes";
-import { NodeDef } from ".";
-import { components } from "@/lib/api/openapi";
-
-const types = ["Text", "Integer", "Float"] as const;
+import { NodeDef, PipelineDataType } from ".";
+import { stringUnionToArray } from "@/lib/util";
 
 type InputNodeType = Node<
 	{
-		type: (typeof types)[number];
+		type: Exclude<
+			PipelineDataType,
+			// Not supported yet
+			`Reference(${number})`
+		>;
 	},
 	"pipelineinput"
 >;
 
+const inputTypes = stringUnionToArray<InputNodeType["data"]["type"]>()(
+	"Text",
+	"Integer",
+	"Float",
+	"Boolean",
+	"Hash",
+	"Blob",
+);
+
 function InputNodeElement({ data, id }: NodeProps<InputNodeType>) {
 	const { deleteElements, getEdges, updateNodeData } = useReactFlow();
 
@@ -28,17 +38,13 @@ function InputNodeElement({ data, id }: NodeProps<InputNodeType>) {
 				<Select
 					label="Data type"
 					placeholder="Pick value"
-					data={dataTypes}
+					data={inputTypes}
 					onChange={(value) => {
 						if (value === null || value === data.type) {
 							return;
 						}
 
-						if (
-							dataTypes.includes(
-								value as components["schemas"]["AttrDataStub"]["type"],
-							)
-						) {
+						if (inputTypes.includes(value as InputNodeType["data"]["type"])) {
 							updateNodeData(id, {
 								type: value,
 							});
@@ -92,8 +98,12 @@ export const InputNode: NodeDef<InputNodeType> = {
 			return null;
 		}
 
-		return {
-			type: data_type.value as (typeof types)[number],
-		};
+		if (
+			!inputTypes.includes(data_type.value as InputNodeType["data"]["type"])
+		) {
+			return null;
+		}
+
+		return { type: data_type.value as InputNodeType["data"]["type"] };
 	},
 };
diff --git a/copperc/src/app/u/pipeline/_nodes/nodes.module.scss b/copperc/src/app/u/pipeline/_nodes/nodes.module.scss
index 07d7466d..4a543256 100644
--- a/copperc/src/app/u/pipeline/_nodes/nodes.module.scss
+++ b/copperc/src/app/u/pipeline/_nodes/nodes.module.scss
@@ -66,8 +66,9 @@
 		flex-direction: column;
 		gap: 0.5rem;
 		align-items: left;
-		justify-content: center;
+		justify-content: start;
 
+		margin: 0.5rem;
 		padding: 0.5rem;
 		min-height: 3rem;
 		flex-grow: 1;
diff --git a/copperc/src/lib/api/openapi.ts b/copperc/src/lib/api/openapi.ts
index ed06eb04..c9f24312 100644
--- a/copperc/src/lib/api/openapi.ts
+++ b/copperc/src/lib/api/openapi.ts
@@ -66,7 +66,7 @@ export interface paths {
 			path?: never;
 			cookie?: never;
 		};
-		/** Get class info */
+		/** List items in this class */
 		get: operations["list_items"];
 		put?: never;
 		post?: never;
@@ -625,6 +625,7 @@ export interface components {
 					class: number;
 					/** Format: int64 */
 					item: number;
+					primary_attr: components["schemas"]["PrimaryAttrData"];
 					/** @enum {string} */
 					type: "Reference";
 			  };
@@ -762,6 +763,57 @@ export interface components {
 				[key: string]: components["schemas"]["NodeJson"];
 			};
 		};
+		PrimaryAttrData:
+			| {
+					/** @enum {string} */
+					type: "NotAvailable";
+			  }
+			| {
+					/** Format: int64 */
+					attr: number;
+					/** @enum {string} */
+					type: "Text";
+					value: string;
+			  }
+			| {
+					/** Format: int64 */
+					attr: number;
+					/** @enum {string} */
+					type: "Integer";
+					/** Format: int64 */
+					value: number;
+			  }
+			| {
+					/** Format: int64 */
+					attr: number;
+					/** @enum {string} */
+					type: "Float";
+					/** Format: double */
+					value: number;
+			  }
+			| {
+					/** Format: int64 */
+					attr: number;
+					/** @enum {string} */
+					type: "Boolean";
+					value: boolean;
+			  }
+			| {
+					/** Format: int64 */
+					attr: number;
+					/** @enum {string} */
+					type: "Hash";
+					value: string;
+			  }
+			| {
+					/** Format: int64 */
+					attr: number;
+					mime: string;
+					/** Format: int64 */
+					size?: number | null;
+					/** @enum {string} */
+					type: "Blob";
+			  };
 		QueuedJobCounts: {
 			/** Format: int64 */
 			build_errors: number;
@@ -819,11 +871,6 @@ export interface components {
 					/** @enum {string} */
 					state: "FailedRunning";
 			  }
-			| {
-					message: string;
-					/** @enum {string} */
-					state: "FailedTransaction";
-			  }
 			| {
 					/** @enum {string} */
 					state: "Success";
diff --git a/copperc/src/lib/attributes/impls/blob.tsx b/copperc/src/lib/attributes/impls/blob.tsx
index 6628bf17..3251cd73 100644
--- a/copperc/src/lib/attributes/impls/blob.tsx
+++ b/copperc/src/lib/attributes/impls/blob.tsx
@@ -18,7 +18,7 @@ export const _blobAttrType: attrTypeInfo<"Blob"> = {
 		form: (params) => BlobForm({ attr_type: { type: "Blob" }, ...params }),
 	},
 
-	table_cell: (value) => {
+	table_cell: ({ value }) => {
 		return (
 			<div
 				style={{
@@ -45,59 +45,68 @@ export const _blobAttrType: attrTypeInfo<"Blob"> = {
 		type: "panel",
 
 		panel_body: (params) => {
-			const data_url = `/api/item/${params.item_id}/attr/${params.attr_id}`;
+			return <BlobPanel {...params} />;
+		},
+	},
+};
 
-			let inner: ReactNode | null = (
-				<_PanelBodyUnknown
-					src={data_url}
-					icon={<X />}
-					attr_value={params.value}
-				/>
-			);
+export function BlobPanel(params: {
+	item_id: number;
+	attr_id: number;
+	value: {
+		mime: string;
+		size?: number | null;
+		type: "Blob";
+	};
+	inner?: boolean;
+}) {
+	const data_url = `/api/item/${params.item_id}/attr/${params.attr_id}`;
 
-			if (params.value.mime != null && params.value.mime.startsWith("image/")) {
-				inner = <_PanelBodyImage src={data_url} attr_value={params.value} />;
-			} else if (
-				params.value.mime != null &&
-				params.value.mime.startsWith("audio/")
-			) {
-				inner = <_PanelBodyAudio src={data_url} attr_value={params.value} />;
-			}
+	let inner: ReactNode | null = (
+		<_PanelBodyUnknown src={data_url} icon={<X />} attr_value={params.value} />
+	);
 
-			return (
-				<div
-					style={{
-						height: "100%",
-						width: "100%",
-						display: "flex",
-						flexDirection: "column",
-					}}
+	if (params.value.mime != null && params.value.mime.startsWith("image/")) {
+		inner = <_PanelBodyImage src={data_url} attr_value={params.value} />;
+	} else if (
+		params.value.mime != null &&
+		params.value.mime.startsWith("audio/")
+	) {
+		inner = <_PanelBodyAudio src={data_url} attr_value={params.value} />;
+	}
+
+	return (
+		<div
+			style={{
+				height: "100%",
+				width: "100%",
+				display: "flex",
+				flexDirection: "column",
+			}}
+		>
+			<div
+				style={{
+					width: "100%",
+					flexGrow: 1,
+					padding: params.inner !== true ? "0.5rem" : undefined,
+					cursor: "zoom-in",
+				}}
+			>
+				<a
+					target="_blank"
+					href={data_url}
+					rel="noopener noreferrer"
+					style={{ width: "100%", height: "100%", cursor: "inherit" }}
 				>
-					<div
-						style={{
-							width: "100%",
-							flexGrow: 1,
-							padding: params.inner !== true ? "0.5rem" : undefined,
-							cursor: "zoom-in",
-						}}
-					>
-						<a
-							target="_blank"
-							href={data_url}
-							rel="noopener noreferrer"
-							style={{ width: "100%", height: "100%", cursor: "inherit" }}
-						>
-							{inner}
-						</a>
-					</div>
-					{params.inner !== true ? (
-						<_PanelBottom attr_value={params.value} />
-					) : null}
-				</div>
-			);
-		},
-	},
-};
+					{inner}
+				</a>
+			</div>
+			{params.inner !== true ? (
+				<_PanelBottom attr_value={params.value} />
+			) : null}
+		</div>
+	);
+}
 
 // Same as basicform, but with the "unique" switch hidden.
 // It has no effect on blobs.
diff --git a/copperc/src/lib/attributes/impls/boolean.tsx b/copperc/src/lib/attributes/impls/boolean.tsx
index 88259063..30e9e955 100644
--- a/copperc/src/lib/attributes/impls/boolean.tsx
+++ b/copperc/src/lib/attributes/impls/boolean.tsx
@@ -11,7 +11,7 @@ export const _booleanAttrType: attrTypeInfo<"Boolean"> = {
 		form: (params) => BasicForm({ attr_type: { type: "Boolean" }, ...params }),
 	},
 
-	table_cell: (value) => {
+	table_cell: ({ value }) => {
 		return (
 			<div
 				style={{
diff --git a/copperc/src/lib/attributes/impls/float.tsx b/copperc/src/lib/attributes/impls/float.tsx
index 0f9ffd07..83dfb551 100644
--- a/copperc/src/lib/attributes/impls/float.tsx
+++ b/copperc/src/lib/attributes/impls/float.tsx
@@ -20,7 +20,7 @@ export const _floatAttrType: attrTypeInfo<"Float"> = {
 		form: (params) => Form(params),
 	},
 
-	table_cell: (value) => {
+	table_cell: ({ value }) => {
 		return (
 			<div
 				style={{
diff --git a/copperc/src/lib/attributes/impls/hash.tsx b/copperc/src/lib/attributes/impls/hash.tsx
index dd9249da..10261801 100644
--- a/copperc/src/lib/attributes/impls/hash.tsx
+++ b/copperc/src/lib/attributes/impls/hash.tsx
@@ -20,8 +20,27 @@ export const _hashAttrType: attrTypeInfo<"Hash"> = {
 		form: (params) => Form(params),
 	},
 
-	table_cell: (value) => {
-		return value.value;
+	table_cell: ({ value }) => {
+		let v = value.value;
+		if (v.length > 10) {
+			v = v.slice(0, 10) + "…";
+		}
+
+		return (
+			<div
+				style={{
+					paddingLeft: "0.5rem",
+					width: "100%",
+					overflow: "hidden",
+					textOverflow: "ellipsis",
+					whiteSpace: "nowrap",
+					color: "var(--mantine-color-white)",
+					fontFamily: "monospace",
+				}}
+			>
+				{v}
+			</div>
+		);
 	},
 
 	editor: {
@@ -34,6 +53,7 @@ export const _hashAttrType: attrTypeInfo<"Hash"> = {
 		new_value: (params) => {
 			return (
 				<Textarea
+					disabled
 					radius="0px"
 					placeholder="no value"
 					autosize
diff --git a/copperc/src/lib/attributes/impls/integer.tsx b/copperc/src/lib/attributes/impls/integer.tsx
index efbbf7cd..649259ab 100644
--- a/copperc/src/lib/attributes/impls/integer.tsx
+++ b/copperc/src/lib/attributes/impls/integer.tsx
@@ -20,7 +20,7 @@ export const _integerAttrType: attrTypeInfo<"Integer"> = {
 		form: (params) => Form(params),
 	},
 
-	table_cell: (value) => {
+	table_cell: ({ value }) => {
 		return (
 			<div
 				style={{
diff --git a/copperc/src/lib/attributes/impls/reference.tsx b/copperc/src/lib/attributes/impls/reference.tsx
index bb3dbabf..05034490 100644
--- a/copperc/src/lib/attributes/impls/reference.tsx
+++ b/copperc/src/lib/attributes/impls/reference.tsx
@@ -9,8 +9,9 @@ import { components } from "@/lib/api/openapi";
 import { edgeclient } from "@/lib/api/client";
 import { useMutation, useQuery } from "@tanstack/react-query";
 import { ReactElement } from "react";
-import { Select, Text } from "@mantine/core";
+import { Select } from "@mantine/core";
 import { useForm, UseFormReturnType } from "@mantine/form";
+import { BlobPanel } from "./blob";
 
 export const _referenceAttrType: attrTypeInfo<"Reference"> = {
 	pretty_name: "Reference",
@@ -20,23 +21,106 @@ export const _referenceAttrType: attrTypeInfo<"Reference"> = {
 		form: (params) => Form(params),
 	},
 
-	table_cell: (value) => {
+	table_cell: ({ dataset, value }) => {
+		const c = dataset.classes.find((x) => x.id === value.class)!;
+
 		return (
-			<Text c="dimmed">
-				Reference to
-				{` #${value.item} of class`}
-				<Text c="dimmed" fs="italic" span>
-					{`#${value.class}`}
-				</Text>
-			</Text>
+			<div
+				style={{
+					paddingLeft: "0.5rem",
+					width: "100%",
+					overflow: "hidden",
+					textOverflow: "ellipsis",
+					whiteSpace: "nowrap",
+					color: "var(--mantine-color-dimmed)",
+					fontStyle: "italic",
+				}}
+			>
+				{`${c.name} #${value.item}`}
+			</div>
 		);
 	},
 
 	editor: {
 		type: "panel",
 
-		panel_body: () => {
-			return "todo-ref";
+		panel_body: (params) => {
+			const pa = params.value.primary_attr;
+
+			if (pa.type === "NotAvailable") {
+				return (
+					<div
+						style={{
+							display: "flex",
+							flexDirection: "column",
+							justifyContent: "center",
+							alignItems: "center",
+
+							paddingLeft: "0.5rem",
+							width: "100%",
+							height: "100%",
+
+							color: "var(--mantine-color-dimmed)",
+							fontStyle: "italic",
+							fontWeight: 500,
+							fontSize: "1.2rem",
+							userSelect: "none",
+						}}
+					>
+						No attribute available
+					</div>
+				);
+			}
+
+			if (pa.type === "Blob") {
+				return (
+					<BlobPanel
+						item_id={params.value.item}
+						attr_id={pa.attr}
+						value={pa}
+						inner={true}
+					/>
+				);
+			}
+
+			let v = <div>UNSET!</div>;
+			if (pa.type === "Boolean") {
+				v = pa.value ? (
+					<span style={{ color: "var(--mantine-color-green-5)" }}>true</span>
+				) : (
+					<span style={{ color: "var(--mantine-color-red-5)" }}>false</span>
+				);
+			} else if (pa.type === "Float" || pa.type === "Integer") {
+				v = <span>{pa.value}</span>;
+			} else if (pa.type === "Hash") {
+				v = <span style={{ fontFamily: "monospace" }}>{pa.value}</span>;
+			} else if (pa.type === "Text") {
+				v = <span>{pa.value}</span>;
+			}
+
+			return (
+				<div
+					style={{
+						display: "flex",
+						flexDirection: "column",
+						justifyContent: "center",
+						alignItems: "center",
+
+						paddingLeft: "0.5rem",
+						width: "100%",
+						height: "100%",
+
+						color: "var(--mantine-color-dimmed)",
+						fontStyle: "italic",
+						fontWeight: 500,
+						fontSize: "1.2rem",
+						userSelect: "none",
+					}}
+				>
+					<div>{pa.type}</div>
+					{v}
+				</div>
+			);
 		},
 	},
 };
diff --git a/copperc/src/lib/attributes/impls/text.tsx b/copperc/src/lib/attributes/impls/text.tsx
index feb98b8d..cc3f3b71 100644
--- a/copperc/src/lib/attributes/impls/text.tsx
+++ b/copperc/src/lib/attributes/impls/text.tsx
@@ -11,7 +11,7 @@ export const _textAttrType: attrTypeInfo<"Text"> = {
 		form: (params) => BasicForm({ attr_type: { type: "Text" }, ...params }),
 	},
 
-	table_cell: (value) => {
+	table_cell: ({ value }) => {
 		return (
 			<div
 				style={{
@@ -37,9 +37,8 @@ export const _textAttrType: attrTypeInfo<"Text"> = {
 					style={{
 						paddingLeft: "0.5rem",
 						width: "100%",
-						overflow: "hidden",
+						overflow: "scroll",
 						textOverflow: "ellipsis",
-						whiteSpace: "nowrap",
 						color: "var(--mantine-color-white)",
 					}}
 				>
@@ -51,6 +50,7 @@ export const _textAttrType: attrTypeInfo<"Text"> = {
 		new_value: (params) => {
 			return (
 				<Textarea
+					disabled
 					radius="0px"
 					placeholder="no value"
 					autosize
diff --git a/copperc/src/lib/attributes/index.ts b/copperc/src/lib/attributes/index.ts
index 4bec11ca..e9a8077f 100644
--- a/copperc/src/lib/attributes/index.ts
+++ b/copperc/src/lib/attributes/index.ts
@@ -8,19 +8,12 @@ import { _integerAttrType } from "./impls/integer";
 import { _hashAttrType } from "./impls/hash";
 import { _referenceAttrType } from "./impls/reference";
 import { components } from "../api/openapi";
+import { stringUnionToArray } from "../util";
 
-export type DataType =
+export type AttrDataType =
 	components["schemas"]["AttributeInfo"]["data_type"]["type"];
 
-// Hack types to enforce `attrTypes`
-type NonEmptyArray<T> = [T, ...T[]];
-type MustInclude<T, U extends T[]> = [T] extends [U[keyof U]] ? U : never;
-function stringUnionToArray<T>() {
-	return <U extends NonEmptyArray<T>>(...elements: MustInclude<T, U>) =>
-		elements;
-}
-
-export const dataTypes = stringUnionToArray<DataType>()(
+export const attrDataTypes = stringUnionToArray<AttrDataType>()(
 	"Text",
 	"Integer",
 	"Float",
@@ -30,7 +23,7 @@ export const dataTypes = stringUnionToArray<DataType>()(
 	"Reference",
 );
 
-export type attrTypeInfo<SerializeAs extends DataType = DataType> = {
+export type attrTypeInfo<SerializeAs extends AttrDataType = AttrDataType> = {
 	// Pretty name to display to user
 	pretty_name: string;
 
@@ -44,9 +37,9 @@ export type attrTypeInfo<SerializeAs extends DataType = DataType> = {
 	// Consumes a function is called whenever parameters change,
 	// returns html that controls this input.
 	create_params: {
-		/// The form we use to create this attr.
-		/// This should contain everything (including buttons),
-		/// except for the attribute type selector.
+		// The form we use to create this attr.
+		// This should contain everything (including buttons),
+		// except for the attribute type selector.
 		form: (params: {
 			dataset_id: number;
 			class_id: number;
@@ -57,12 +50,14 @@ export type attrTypeInfo<SerializeAs extends DataType = DataType> = {
 
 	// TODO: what does null mean?
 	// TODO: stricter types
-	table_cell: (
+	table_cell: (params: {
 		value: Extract<
 			components["schemas"]["ItemAttrData"],
 			{ type: SerializeAs }
-		>,
-	) => null | ReactNode;
+		>;
+
+		dataset: components["schemas"]["DatasetInfo"];
+	}) => null | ReactNode;
 
 	editor:
 		| {
@@ -115,7 +110,7 @@ export type attrTypeInfo<SerializeAs extends DataType = DataType> = {
 		  };
 };
 
-export function getAttrTypeInfo<T extends DataType = DataType>(
+export function getAttrTypeInfo<T extends AttrDataType = AttrDataType>(
 	type: T,
 ): attrTypeInfo<T> {
 	const x = {
diff --git a/copperc/src/lib/util.ts b/copperc/src/lib/util.ts
new file mode 100644
index 00000000..6f85de8c
--- /dev/null
+++ b/copperc/src/lib/util.ts
@@ -0,0 +1,13 @@
+// Hack types to enforce `attrTypes`
+type NonEmptyArray<T> = [T, ...T[]];
+type MustInclude<T, U extends T[]> = [T] extends [U[keyof U]] ? U : never;
+
+/**
+ * Hack that allows us to create a type-checked array
+ * that contains every variant of a string union.
+ */
+// TODO: uniqueness
+export function stringUnionToArray<T>() {
+	return <U extends NonEmptyArray<T>>(...elements: MustInclude<T, U>) =>
+		elements;
+}
diff --git a/copperd/Cargo.lock b/copperd/Cargo.lock
index 9f5a05b5..b56e6d0a 100644
--- a/copperd/Cargo.lock
+++ b/copperd/Cargo.lock
@@ -81,18 +81,6 @@ dependencies = [
  "password-hash",
 ]
 
-[[package]]
-name = "async-broadcast"
-version = "0.7.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "20cd0e2e25ea8e5f7e9df04578dc6cf5c83577fd09b1a46aaf5c85e1c33f2a7e"
-dependencies = [
- "event-listener 5.3.1",
- "event-listener-strategy",
- "futures-core",
- "pin-project-lite",
-]
-
 [[package]]
 name = "async-trait"
 version = "0.1.81"
@@ -720,15 +708,6 @@ dependencies = [
  "windows-targets 0.52.5",
 ]
 
-[[package]]
-name = "concurrent-queue"
-version = "2.5.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4ca0197aee26d1ae37445ee532fefce43251d24cc7c166799f4d46817f1d3973"
-dependencies = [
- "crossbeam-utils",
-]
-
 [[package]]
 name = "const-oid"
 version = "0.9.6"
@@ -811,12 +790,12 @@ dependencies = [
 name = "copper-piper"
 version = "0.1.0"
 dependencies = [
- "async-broadcast",
  "async-trait",
  "copper-itemdb",
  "copper-util",
  "serde",
  "smartstring",
+ "sqlx",
  "thiserror 2.0.1",
  "tokio",
  "utoipa",
@@ -1179,27 +1158,6 @@ version = "2.5.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0206175f82b8d6bf6652ff7d71a1e27fd2e4efde587fd368662814d6ec1d9ce0"
 
-[[package]]
-name = "event-listener"
-version = "5.3.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6032be9bd27023a771701cc49f9f053c751055f71efb2e0ae5c15809093675ba"
-dependencies = [
- "concurrent-queue",
- "parking",
- "pin-project-lite",
-]
-
-[[package]]
-name = "event-listener-strategy"
-version = "0.5.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0f214dc438f977e6d4e3500aaa277f5ad94ca83fbbd9b1a15713ce2344ccc5a1"
-dependencies = [
- "event-listener 5.3.1",
- "pin-project-lite",
-]
-
 [[package]]
 name = "fastrand"
 version = "2.1.0"
@@ -1880,10 +1838,8 @@ dependencies = [
 name = "nodes-audiofile"
 version = "0.1.0"
 dependencies = [
- "async-broadcast",
  "async-trait",
  "base64 0.22.1",
- "copper-itemdb",
  "copper-piper",
  "copper-util",
  "itertools",
@@ -1907,9 +1863,9 @@ dependencies = [
  "copper-util",
  "md5",
  "rand",
- "serde_json",
  "sha2",
  "smartstring",
+ "sqlx",
  "tokio",
  "tracing",
 ]
@@ -2071,12 +2027,6 @@ dependencies = [
  "sha2",
 ]
 
-[[package]]
-name = "parking"
-version = "2.2.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f38d5652c16fde515bb1ecef450ab0f6a219d619a7274976324d5e377f7dceba"
-
 [[package]]
 name = "parking_lot"
 version = "0.12.3"
@@ -2188,6 +2138,7 @@ dependencies = [
  "nodes-basic",
  "serde",
  "smartstring",
+ "sqlx",
  "thiserror 2.0.1",
  "tokio",
  "tracing",
@@ -2987,7 +2938,7 @@ dependencies = [
  "crc",
  "crossbeam-queue",
  "either",
- "event-listener 2.5.3",
+ "event-listener",
  "futures-channel",
  "futures-core",
  "futures-intrusive",
diff --git a/copperd/Cargo.toml b/copperd/Cargo.toml
index f9612b78..cfd0e8c0 100644
--- a/copperd/Cargo.toml
+++ b/copperd/Cargo.toml
@@ -145,9 +145,6 @@ serde_with = "3.8.1"
 utoipa = { version = "5.0.0-alpha.0", features = ["axum_extras"] }
 thiserror = "2.0.1"
 
-# Because we can't clone tokio's `broadcast::Receiver`
-async-broadcast = "0.7.1"
-
 
 [workspace.dependencies.time]
 version = "0.3.36"
diff --git a/copperd/bin/edged/src/api/attribute/del.rs b/copperd/bin/edged/src/api/attribute/del.rs
index c5703b72..d4d67050 100644
--- a/copperd/bin/edged/src/api/attribute/del.rs
+++ b/copperd/bin/edged/src/api/attribute/del.rs
@@ -6,14 +6,12 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::{
-	client::ItemdbClient,
-	errors::{
-		attribute::{DeleteAttributeError, GetAttributeError},
-		class::GetClassError,
-		dataset::GetDatasetError,
-	},
+use copper_itemdb::client::errors::{
+	attribute::{DeleteAttributeError, GetAttributeError},
+	class::GetClassError,
+	dataset::GetDatasetError,
 };
+use sqlx::Acquire;
 use tracing::error;
 
 use crate::api::RouterState;
@@ -30,9 +28,9 @@ use crate::api::RouterState;
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn del_attribute<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn del_attribute<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(attribute_id): Path<i64>,
 ) -> Response {
 	let user = match state.auth.auth_or_logout(&state, &jar).await {
@@ -40,7 +38,35 @@ pub(super) async fn del_attribute<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		Ok(user) => user,
 	};
 
-	let attr = match state.itemdb_client.get_attribute(attribute_id.into()).await {
+	let mut conn = match state.itemdb_client.new_connection().await {
+		Ok(x) => x,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let mut trans = match conn.begin().await {
+		Ok(y) => y,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let attr = match state
+		.itemdb_client
+		.get_attribute(&mut trans, attribute_id.into())
+		.await
+	{
 		Ok(x) => x,
 
 		Err(GetAttributeError::NotFound) => {
@@ -57,7 +83,7 @@ pub(super) async fn del_attribute<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		}
 	};
 
-	let class = match state.itemdb_client.get_class(attr.class).await {
+	let class = match state.itemdb_client.get_class(&mut trans, attr.class).await {
 		Ok(x) => x,
 
 		// In theory unreachable, but possible with unlucky timing
@@ -75,7 +101,11 @@ pub(super) async fn del_attribute<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		}
 	};
 
-	match state.itemdb_client.get_dataset(class.dataset).await {
+	match state
+		.itemdb_client
+		.get_dataset(&mut trans, class.dataset)
+		.await
+	{
 		Ok(x) => {
 			// We can only modify our own datasets
 			if x.owner != user.id {
@@ -98,10 +128,23 @@ pub(super) async fn del_attribute<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		}
 	};
 
-	let res = state.itemdb_client.del_attribute(attribute_id.into()).await;
+	let res = state
+		.itemdb_client
+		.del_attribute(&mut trans, attribute_id.into())
+		.await;
 
 	return match res {
-		Ok(()) => StatusCode::OK.into_response(),
+		Ok(()) => match trans.commit().await {
+			Ok(()) => StatusCode::OK.into_response(),
+			Err(error) => {
+				error!(message = "Error while committing transaction", ?error);
+				return (
+					StatusCode::INTERNAL_SERVER_ERROR,
+					Json("Internal server error"),
+				)
+					.into_response();
+			}
+		},
 
 		Err(DeleteAttributeError::DbError(error)) => {
 			error!(message = "Error in itemdb client", ?error);
diff --git a/copperd/bin/edged/src/api/attribute/get.rs b/copperd/bin/edged/src/api/attribute/get.rs
index 1be7ea2a..f89dcb9e 100644
--- a/copperd/bin/edged/src/api/attribute/get.rs
+++ b/copperd/bin/edged/src/api/attribute/get.rs
@@ -7,10 +7,10 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::{
-	client::ItemdbClient,
-	errors::{attribute::GetAttributeError, class::GetClassError, dataset::GetDatasetError},
+use copper_itemdb::client::errors::{
+	attribute::GetAttributeError, class::GetClassError, dataset::GetDatasetError,
 };
+use sqlx::Acquire;
 use tracing::error;
 
 /// Get attribute info
@@ -26,9 +26,9 @@ use tracing::error;
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn get_attribute<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn get_attribute<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(attribute_id): Path<i64>,
 ) -> Response {
 	let user = match state.auth.auth_or_logout(&state, &jar).await {
@@ -36,7 +36,35 @@ pub(super) async fn get_attribute<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		Ok(user) => user,
 	};
 
-	let attr = match state.itemdb_client.get_attribute(attribute_id.into()).await {
+	let mut conn = match state.itemdb_client.new_connection().await {
+		Ok(x) => x,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let mut trans = match conn.begin().await {
+		Ok(y) => y,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let attr = match state
+		.itemdb_client
+		.get_attribute(&mut trans, attribute_id.into())
+		.await
+	{
 		Ok(x) => x,
 
 		Err(GetAttributeError::NotFound) => {
@@ -53,7 +81,7 @@ pub(super) async fn get_attribute<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		}
 	};
 
-	let class = match state.itemdb_client.get_class(attr.class).await {
+	let class = match state.itemdb_client.get_class(&mut trans, attr.class).await {
 		Ok(x) => x,
 
 		// In theory unreachable, but possible with unlucky timing
@@ -71,7 +99,11 @@ pub(super) async fn get_attribute<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		}
 	};
 
-	match state.itemdb_client.get_dataset(class.dataset).await {
+	match state
+		.itemdb_client
+		.get_dataset(&mut trans, class.dataset)
+		.await
+	{
 		Ok(x) => {
 			// We can only modify our own datasets
 			if x.owner != user.id {
diff --git a/copperd/bin/edged/src/api/attribute/mod.rs b/copperd/bin/edged/src/api/attribute/mod.rs
index c6103330..28ba3297 100644
--- a/copperd/bin/edged/src/api/attribute/mod.rs
+++ b/copperd/bin/edged/src/api/attribute/mod.rs
@@ -4,7 +4,6 @@ use axum::{
 	routing::{delete, get, patch},
 	Router,
 };
-use copper_itemdb::client::base::client::ItemdbClient;
 use utoipa::OpenApi;
 
 mod del;
@@ -23,8 +22,7 @@ use rename::*;
 )]
 pub(super) struct AttributeApi;
 
-pub(super) fn router<Client: DatabaseClient + 'static, Itemdb: ItemdbClient + 'static>(
-) -> Router<RouterState<Client, Itemdb>> {
+pub(super) fn router<Client: DatabaseClient + 'static>() -> Router<RouterState<Client>> {
 	Router::new()
 		.route("/:attribute_id", get(get_attribute))
 		.route("/:attribute_id", delete(del_attribute))
diff --git a/copperd/bin/edged/src/api/attribute/rename.rs b/copperd/bin/edged/src/api/attribute/rename.rs
index 40eaead6..0066ce42 100644
--- a/copperd/bin/edged/src/api/attribute/rename.rs
+++ b/copperd/bin/edged/src/api/attribute/rename.rs
@@ -6,15 +6,13 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::{
-	client::ItemdbClient,
-	errors::{
-		attribute::{GetAttributeError, RenameAttributeError},
-		class::GetClassError,
-		dataset::GetDatasetError,
-	},
+use copper_itemdb::client::errors::{
+	attribute::{GetAttributeError, RenameAttributeError},
+	class::GetClassError,
+	dataset::GetDatasetError,
 };
 use serde::Deserialize;
+use sqlx::Acquire;
 use tracing::error;
 use utoipa::ToSchema;
 
@@ -38,9 +36,9 @@ pub(super) struct RenameAttributeRequest {
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn rename_attribute<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn rename_attribute<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(attribute_id): Path<i64>,
 	Json(payload): Json<RenameAttributeRequest>,
 ) -> Response {
@@ -49,7 +47,35 @@ pub(super) async fn rename_attribute<Client: DatabaseClient, Itemdb: ItemdbClien
 		Ok(user) => user,
 	};
 
-	let attr = match state.itemdb_client.get_attribute(attribute_id.into()).await {
+	let mut conn = match state.itemdb_client.new_connection().await {
+		Ok(x) => x,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let mut trans = match conn.begin().await {
+		Ok(y) => y,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let attr = match state
+		.itemdb_client
+		.get_attribute(&mut trans, attribute_id.into())
+		.await
+	{
 		Ok(x) => x,
 
 		Err(GetAttributeError::NotFound) => {
@@ -66,7 +92,7 @@ pub(super) async fn rename_attribute<Client: DatabaseClient, Itemdb: ItemdbClien
 		}
 	};
 
-	let class = match state.itemdb_client.get_class(attr.class).await {
+	let class = match state.itemdb_client.get_class(&mut trans, attr.class).await {
 		Ok(x) => x,
 
 		// In theory unreachable, but possible with unlucky timing
@@ -84,7 +110,11 @@ pub(super) async fn rename_attribute<Client: DatabaseClient, Itemdb: ItemdbClien
 		}
 	};
 
-	match state.itemdb_client.get_dataset(class.dataset).await {
+	match state
+		.itemdb_client
+		.get_dataset(&mut trans, class.dataset)
+		.await
+	{
 		Ok(x) => {
 			// We can only modify our own datasets
 			if x.owner != user.id {
@@ -109,11 +139,21 @@ pub(super) async fn rename_attribute<Client: DatabaseClient, Itemdb: ItemdbClien
 
 	let res = state
 		.itemdb_client
-		.rename_attribute(attribute_id.into(), &payload.new_name)
+		.rename_attribute(&mut trans, attribute_id.into(), &payload.new_name)
 		.await;
 
 	return match res {
-		Ok(()) => StatusCode::OK.into_response(),
+		Ok(()) => match trans.commit().await {
+			Ok(()) => StatusCode::OK.into_response(),
+			Err(error) => {
+				error!(message = "Error while committing transaction", ?error);
+				return (
+					StatusCode::INTERNAL_SERVER_ERROR,
+					Json("Internal server error"),
+				)
+					.into_response();
+			}
+		},
 
 		Err(RenameAttributeError::UniqueViolation) => {
 			return (
diff --git a/copperd/bin/edged/src/api/class/add_attribute.rs b/copperd/bin/edged/src/api/class/add_attribute.rs
index ad5f0767..eb89e9fc 100644
--- a/copperd/bin/edged/src/api/class/add_attribute.rs
+++ b/copperd/bin/edged/src/api/class/add_attribute.rs
@@ -7,13 +7,13 @@ use axum::{
 };
 use axum_extra::extract::CookieJar;
 use copper_itemdb::{
-	client::base::{
-		client::ItemdbClient,
-		errors::{attribute::AddAttributeError, class::GetClassError, dataset::GetDatasetError},
+	client::errors::{
+		attribute::AddAttributeError, class::GetClassError, dataset::GetDatasetError,
 	},
 	AttrDataStub, AttributeOptions,
 };
 use serde::{Deserialize, Serialize};
+use sqlx::Acquire;
 use tracing::error;
 use utoipa::ToSchema;
 
@@ -41,9 +41,9 @@ pub(super) struct NewAttributeRequest {
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn add_attribute<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn add_attribute<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(class_id): Path<i64>,
 	Json(payload): Json<NewAttributeRequest>,
 ) -> Response {
@@ -52,7 +52,35 @@ pub(super) async fn add_attribute<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		Ok(user) => user,
 	};
 
-	let class = match state.itemdb_client.get_class(class_id.into()).await {
+	let mut conn = match state.itemdb_client.new_connection().await {
+		Ok(x) => x,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let mut trans = match conn.begin().await {
+		Ok(y) => y,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let class = match state
+		.itemdb_client
+		.get_class(&mut trans, class_id.into())
+		.await
+	{
 		Ok(x) => x,
 
 		Err(GetClassError::NotFound) => {
@@ -69,7 +97,11 @@ pub(super) async fn add_attribute<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		}
 	};
 
-	match state.itemdb_client.get_dataset(class.dataset).await {
+	match state
+		.itemdb_client
+		.get_dataset(&mut trans, class.dataset)
+		.await
+	{
 		Ok(x) => {
 			// We can only modify our own datasets
 			if x.owner != user.id {
@@ -95,6 +127,7 @@ pub(super) async fn add_attribute<Client: DatabaseClient, Itemdb: ItemdbClient>(
 	let res = state
 		.itemdb_client
 		.add_attribute(
+			&mut trans,
 			class_id.into(),
 			&payload.name,
 			payload.data_type,
@@ -103,7 +136,21 @@ pub(super) async fn add_attribute<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		.await;
 
 	return match res {
-		Ok(x) => (StatusCode::OK, Json(x)).into_response(),
+		Ok(x) => {
+			match trans.commit().await {
+				Ok(()) => {}
+				Err(error) => {
+					error!(message = "Error while committing transaction", ?error);
+					return (
+						StatusCode::INTERNAL_SERVER_ERROR,
+						Json("Internal server error"),
+					)
+						.into_response();
+				}
+			};
+
+			(StatusCode::OK, Json(x)).into_response()
+		}
 
 		Err(AddAttributeError::NoSuchClass) => {
 			return (StatusCode::NOT_FOUND, Json("Class not found")).into_response();
diff --git a/copperd/bin/edged/src/api/class/del.rs b/copperd/bin/edged/src/api/class/del.rs
index ef792061..99b4646d 100644
--- a/copperd/bin/edged/src/api/class/del.rs
+++ b/copperd/bin/edged/src/api/class/del.rs
@@ -6,13 +6,11 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::{
-	client::ItemdbClient,
-	errors::{
-		class::{DeleteClassError, GetClassError},
-		dataset::GetDatasetError,
-	},
+use copper_itemdb::client::errors::{
+	class::{DeleteClassError, GetClassError},
+	dataset::GetDatasetError,
 };
+use sqlx::Acquire;
 use tracing::error;
 
 use crate::api::RouterState;
@@ -30,9 +28,9 @@ use crate::api::RouterState;
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn del_class<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn del_class<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(class_id): Path<i64>,
 ) -> Response {
 	let user = match state.auth.auth_or_logout(&state, &jar).await {
@@ -40,7 +38,35 @@ pub(super) async fn del_class<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		Ok(user) => user,
 	};
 
-	let class = match state.itemdb_client.get_class(class_id.into()).await {
+	let mut conn = match state.itemdb_client.new_connection().await {
+		Ok(x) => x,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let mut trans = match conn.begin().await {
+		Ok(y) => y,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let class = match state
+		.itemdb_client
+		.get_class(&mut trans, class_id.into())
+		.await
+	{
 		Ok(x) => x,
 
 		Err(GetClassError::NotFound) => {
@@ -57,7 +83,11 @@ pub(super) async fn del_class<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		}
 	};
 
-	match state.itemdb_client.get_dataset(class.dataset).await {
+	match state
+		.itemdb_client
+		.get_dataset(&mut trans, class.dataset)
+		.await
+	{
 		Ok(x) => {
 			// We can only modify our own datasets
 			if x.owner != user.id {
@@ -80,10 +110,23 @@ pub(super) async fn del_class<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		}
 	};
 
-	let res = state.itemdb_client.del_class(class_id.into()).await;
+	let res = state
+		.itemdb_client
+		.del_class(&mut trans, class_id.into())
+		.await;
 
 	return match res {
-		Ok(()) => StatusCode::OK.into_response(),
+		Ok(()) => match trans.commit().await {
+			Ok(()) => StatusCode::OK.into_response(),
+			Err(error) => {
+				error!(message = "Error while committing transaction", ?error);
+				return (
+					StatusCode::INTERNAL_SERVER_ERROR,
+					Json("Internal server error"),
+				)
+					.into_response();
+			}
+		},
 
 		Err(DeleteClassError::DbError(error)) => {
 			error!(message = "Error in itemdb client", ?error);
diff --git a/copperd/bin/edged/src/api/class/get.rs b/copperd/bin/edged/src/api/class/get.rs
index 9513316a..f7dd1a19 100644
--- a/copperd/bin/edged/src/api/class/get.rs
+++ b/copperd/bin/edged/src/api/class/get.rs
@@ -7,10 +7,8 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::{
-	client::ItemdbClient,
-	errors::{class::GetClassError, dataset::GetDatasetError},
-};
+use copper_itemdb::client::errors::{class::GetClassError, dataset::GetDatasetError};
+use sqlx::Acquire;
 use tracing::error;
 
 /// Get class info
@@ -27,9 +25,9 @@ use tracing::error;
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn get_class<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn get_class<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(class_id): Path<i64>,
 ) -> Response {
 	let user = match state.auth.auth_or_logout(&state, &jar).await {
@@ -37,7 +35,35 @@ pub(super) async fn get_class<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		Ok(user) => user,
 	};
 
-	let class = match state.itemdb_client.get_class(class_id.into()).await {
+	let mut conn = match state.itemdb_client.new_connection().await {
+		Ok(x) => x,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let mut trans = match conn.begin().await {
+		Ok(y) => y,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let class = match state
+		.itemdb_client
+		.get_class(&mut trans, class_id.into())
+		.await
+	{
 		Ok(x) => x,
 
 		Err(GetClassError::NotFound) => {
@@ -54,7 +80,11 @@ pub(super) async fn get_class<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		}
 	};
 
-	match state.itemdb_client.get_dataset(class.dataset).await {
+	match state
+		.itemdb_client
+		.get_dataset(&mut trans, class.dataset)
+		.await
+	{
 		Ok(x) => {
 			// We can only modify our own datasets
 			if x.owner != user.id {
diff --git a/copperd/bin/edged/src/api/class/items.rs b/copperd/bin/edged/src/api/class/items.rs
index 717c4a16..575a84d0 100644
--- a/copperd/bin/edged/src/api/class/items.rs
+++ b/copperd/bin/edged/src/api/class/items.rs
@@ -10,21 +10,23 @@ use axum::{
 };
 use axum_extra::extract::CookieJar;
 use copper_itemdb::{
-	client::base::{
-		client::ItemdbClient,
-		errors::{
-			class::GetClassError,
-			dataset::GetDatasetError,
-			item::{CountItemsError, ListItemsError},
-		},
+	client::errors::{
+		class::{ClassPrimaryAttributeError, GetClassError},
+		dataset::GetDatasetError,
+		item::{CountItemsError, GetItemError, ListItemsError},
 	},
 	AttrData, AttributeId, ClassId, ItemId,
 };
 use itertools::Itertools;
 use serde::{Deserialize, Serialize};
+use sqlx::{Acquire, Transaction};
 use tracing::error;
 use utoipa::{IntoParams, ToSchema};
 
+//
+// MARK: itemattrdata
+//
+
 /// Attribute data returned to the user
 #[derive(Debug, Clone, Serialize, ToSchema)]
 #[serde(tag = "type")]
@@ -60,15 +62,36 @@ pub(super) enum ItemAttrData {
 
 		#[schema(value_type = i64)]
 		item: ItemId,
+
+		primary_attr: PrimaryAttrData,
 	},
 }
 
 impl ItemAttrData {
-	async fn from_attr_data<Client: DatabaseClient, Itemdb: ItemdbClient>(
-		state: &RouterState<Client, Itemdb>,
+	async fn from_attr_data<Client: DatabaseClient>(
+		state: &RouterState<Client>,
 		value: AttrData,
+		trans: &mut Transaction<'_, sqlx::Postgres>,
 	) -> Result<Self, Response> {
 		Ok(match value {
+			//
+			// Easy
+			//
+			AttrData::Integer { value, .. } => Self::Integer { value },
+			AttrData::Float { value, .. } => Self::Float { value },
+			AttrData::Boolean { value } => Self::Boolean { value },
+
+			AttrData::Text { value } => Self::Text {
+				value: value.into(),
+			},
+
+			AttrData::Hash { data, .. } => Self::Hash {
+				value: data.into_iter().map(|x| format!("{x:02X?}")).join(""),
+			},
+
+			//
+			// MARK: blob
+			//
 			AttrData::Blob { bucket, key } => {
 				let meta = match state
 					.s3_client
@@ -91,18 +114,176 @@ impl ItemAttrData {
 					size: meta.size,
 				}
 			}
-			AttrData::Integer { value, .. } => ItemAttrData::Integer { value },
-			AttrData::Float { value, .. } => ItemAttrData::Float { value },
-			AttrData::Boolean { value } => ItemAttrData::Boolean { value },
-			AttrData::Reference { class, item } => ItemAttrData::Reference { class, item },
 
-			AttrData::Text { value } => ItemAttrData::Text {
+			//
+			// MARK: reference
+			//
+			AttrData::Reference { class, item } => Self::Reference {
+				class,
+				item,
+				primary_attr: match state.itemdb_client.class_primary_attr(trans, class).await {
+					Ok(primary_attr) => {
+						if let Some(primary_attr) = primary_attr {
+							let value = state.itemdb_client.get_item(trans, item).await;
+
+							match value {
+								Ok(value) => {
+									PrimaryAttrData::from_attr_data(
+										state,
+										primary_attr.id,
+										value
+											.attribute_values
+											.get(&primary_attr.id)
+											.unwrap()
+											.clone(),
+									)
+									.await?
+								}
+
+								Err(GetItemError::NotFound) => {
+									return Err(StatusCode::NOT_FOUND.into_response())
+								}
+
+								Err(GetItemError::DbError(error)) => {
+									error!(message = "Error in itemdb client", ?error);
+									return Err((
+										StatusCode::INTERNAL_SERVER_ERROR,
+										Json("Internal server error"),
+									)
+										.into_response());
+								}
+							}
+						} else {
+							PrimaryAttrData::NotAvailable
+						}
+					}
+
+					Err(ClassPrimaryAttributeError::NotFound) => {
+						return Err(StatusCode::NOT_FOUND.into_response());
+					}
+
+					Err(ClassPrimaryAttributeError::DbError(error)) => {
+						error!(message = "Error in itemdb client", ?error);
+						return Err((
+							StatusCode::INTERNAL_SERVER_ERROR,
+							Json("Internal server error"),
+						)
+							.into_response());
+					}
+				},
+			},
+		})
+	}
+}
+
+//
+// MARK: primaryattrdata
+//
+
+// Almost identical to [`ItemAttrData`], but excluding references.
+// Used inside the reference variant of [`ItemAttrData`].
+#[derive(Debug, Clone, Serialize, ToSchema)]
+#[serde(tag = "type")]
+pub(super) enum PrimaryAttrData {
+	NotAvailable,
+	Text {
+		#[schema(value_type = i64)]
+		attr: AttributeId,
+		value: String,
+	},
+
+	Integer {
+		#[schema(value_type = i64)]
+		attr: AttributeId,
+		value: i64,
+	},
+
+	Float {
+		#[schema(value_type = i64)]
+		attr: AttributeId,
+		value: f64,
+	},
+
+	Boolean {
+		#[schema(value_type = i64)]
+		attr: AttributeId,
+		value: bool,
+	},
+
+	Hash {
+		#[schema(value_type = i64)]
+		attr: AttributeId,
+		value: String,
+	},
+
+	Blob {
+		#[schema(value_type = i64)]
+		attr: AttributeId,
+
+		mime: String,
+		size: Option<i64>,
+	},
+}
+
+impl PrimaryAttrData {
+	async fn from_attr_data<Client: DatabaseClient>(
+		state: &RouterState<Client>,
+		attr: AttributeId,
+		value: AttrData,
+	) -> Result<Self, Response> {
+		Ok(match value {
+			//
+			// Easy
+			//
+			AttrData::Integer { value, .. } => Self::Integer { value, attr },
+			AttrData::Float { value, .. } => Self::Float { value, attr },
+			AttrData::Boolean { value } => Self::Boolean { value, attr },
+
+			AttrData::Text { value } => Self::Text {
 				value: value.into(),
+				attr,
 			},
 
-			AttrData::Hash { data, .. } => ItemAttrData::Hash {
+			AttrData::Hash { data, .. } => Self::Hash {
 				value: data.into_iter().map(|x| format!("{x:02X?}")).join(""),
+				attr,
 			},
+
+			//
+			// MARK: blob
+			//
+			AttrData::Blob { bucket, key } => {
+				let meta = match state
+					.s3_client
+					.get_object_metadata(bucket.as_str(), key.as_str())
+					.await
+				{
+					Ok(x) => x,
+					Err(error) => {
+						error!(message = "Error in itemdb client", ?error);
+						return Err((
+							StatusCode::INTERNAL_SERVER_ERROR,
+							Json("Internal server error"),
+						)
+							.into_response());
+					}
+				};
+
+				Self::Blob {
+					mime: meta.mime.to_string(),
+					size: meta.size,
+					attr,
+				}
+			}
+
+			AttrData::Reference { .. } => {
+				error!(message = "Tried to put a reference in a reference");
+				return Err((
+					StatusCode::INTERNAL_SERVER_ERROR,
+					Json("Internal server error"),
+				)
+					.into_response());
+			}
 		})
 	}
 }
@@ -135,7 +316,11 @@ pub(super) struct PaginateParams {
 	count: usize,
 }
 
-/// Get class info
+//
+// MARK: route
+//
+
+/// List items in this class
 #[utoipa::path(
 	get,
 	path = "/{class_id}/items",
@@ -150,9 +335,9 @@ pub(super) struct PaginateParams {
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn list_items<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn list_items<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Query(paginate): Query<PaginateParams>,
 	Path(class_id): Path<i64>,
 ) -> Response {
@@ -161,7 +346,35 @@ pub(super) async fn list_items<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		Ok(user) => user,
 	};
 
-	let class = match state.itemdb_client.get_class(class_id.into()).await {
+	let mut conn = match state.itemdb_client.new_connection().await {
+		Ok(x) => x,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let mut trans = match conn.begin().await {
+		Ok(y) => y,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let class = match state
+		.itemdb_client
+		.get_class(&mut trans, class_id.into())
+		.await
+	{
 		Ok(x) => x,
 
 		Err(GetClassError::NotFound) => return StatusCode::NOT_FOUND.into_response(),
@@ -176,7 +389,11 @@ pub(super) async fn list_items<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		}
 	};
 
-	match state.itemdb_client.get_dataset(class.dataset).await {
+	match state
+		.itemdb_client
+		.get_dataset(&mut trans, class.dataset)
+		.await
+	{
 		Ok(x) => {
 			// We can only modify our own class
 			if x.owner != user.id {
@@ -199,7 +416,7 @@ pub(super) async fn list_items<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		}
 	};
 
-	let total = match state.itemdb_client.count_items(class.id).await {
+	let total = match state.itemdb_client.count_items(&mut trans, class.id).await {
 		Ok(x) => x,
 
 		// In theory unreachable, but possible with unlucky timing
@@ -219,7 +436,7 @@ pub(super) async fn list_items<Client: DatabaseClient, Itemdb: ItemdbClient>(
 
 	match state
 		.itemdb_client
-		.list_items(class.id, paginate.skip, paginate.count)
+		.list_items(&mut trans, class.id, paginate.skip, paginate.count)
 		.await
 	{
 		Ok(x) => {
@@ -228,7 +445,7 @@ pub(super) async fn list_items<Client: DatabaseClient, Itemdb: ItemdbClient>(
 			for i in x {
 				let mut attribute_values = BTreeMap::new();
 				for (attr_id, data) in i.attribute_values {
-					match ItemAttrData::from_attr_data(&state, data).await {
+					match ItemAttrData::from_attr_data(&state, data, &mut trans).await {
 						Ok(x) => {
 							attribute_values.insert(attr_id, x);
 						}
diff --git a/copperd/bin/edged/src/api/class/mod.rs b/copperd/bin/edged/src/api/class/mod.rs
index 194b8c72..efd69691 100644
--- a/copperd/bin/edged/src/api/class/mod.rs
+++ b/copperd/bin/edged/src/api/class/mod.rs
@@ -4,7 +4,6 @@ use axum::{
 	routing::{delete, get, patch, post},
 	Router,
 };
-use copper_itemdb::client::base::client::ItemdbClient;
 use utoipa::OpenApi;
 
 mod add_attribute;
@@ -28,13 +27,13 @@ use rename::*;
 		NewAttributeRequest,
 		ItemlistItemInfo,
 		ItemAttrData,
+		PrimaryAttrData,
 		ItemListResponse
 	))
 )]
 pub(super) struct ClassApi;
 
-pub(super) fn router<Client: DatabaseClient + 'static, Itemdb: ItemdbClient + 'static>(
-) -> Router<RouterState<Client, Itemdb>> {
+pub(super) fn router<Client: DatabaseClient + 'static>() -> Router<RouterState<Client>> {
 	Router::new()
 		.route("/:class_id", get(get_class))
 		.route("/:class_id/items", get(list_items))
diff --git a/copperd/bin/edged/src/api/class/rename.rs b/copperd/bin/edged/src/api/class/rename.rs
index 46fa8e29..8da6715d 100644
--- a/copperd/bin/edged/src/api/class/rename.rs
+++ b/copperd/bin/edged/src/api/class/rename.rs
@@ -6,14 +6,12 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::{
-	client::ItemdbClient,
-	errors::{
-		class::{GetClassError, RenameClassError},
-		dataset::GetDatasetError,
-	},
+use copper_itemdb::client::errors::{
+	class::{GetClassError, RenameClassError},
+	dataset::GetDatasetError,
 };
 use serde::Deserialize;
+use sqlx::Acquire;
 use tracing::error;
 use utoipa::ToSchema;
 
@@ -38,9 +36,9 @@ pub(super) struct RenameClassRequest {
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn rename_class<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn rename_class<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(class_id): Path<i64>,
 	Json(payload): Json<RenameClassRequest>,
 ) -> Response {
@@ -49,7 +47,35 @@ pub(super) async fn rename_class<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		Ok(user) => user,
 	};
 
-	let class = match state.itemdb_client.get_class(class_id.into()).await {
+	let mut conn = match state.itemdb_client.new_connection().await {
+		Ok(x) => x,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let mut trans = match conn.begin().await {
+		Ok(y) => y,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let class = match state
+		.itemdb_client
+		.get_class(&mut trans, class_id.into())
+		.await
+	{
 		Ok(x) => x,
 
 		Err(GetClassError::NotFound) => {
@@ -66,7 +92,11 @@ pub(super) async fn rename_class<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		}
 	};
 
-	match state.itemdb_client.get_dataset(class.dataset).await {
+	match state
+		.itemdb_client
+		.get_dataset(&mut trans, class.dataset)
+		.await
+	{
 		Ok(x) => {
 			// We can only modify our own datasets
 			if x.owner != user.id {
@@ -91,11 +121,21 @@ pub(super) async fn rename_class<Client: DatabaseClient, Itemdb: ItemdbClient>(
 
 	let res = state
 		.itemdb_client
-		.rename_class(class_id.into(), &payload.new_name)
+		.rename_class(&mut trans, class_id.into(), &payload.new_name)
 		.await;
 
 	return match res {
-		Ok(()) => StatusCode::OK.into_response(),
+		Ok(()) => match trans.commit().await {
+			Ok(()) => StatusCode::OK.into_response(),
+			Err(error) => {
+				error!(message = "Error while committing transaction", ?error);
+				return (
+					StatusCode::INTERNAL_SERVER_ERROR,
+					Json("Internal server error"),
+				)
+					.into_response();
+			}
+		},
 
 		Err(RenameClassError::UniqueViolation) => {
 			return (
diff --git a/copperd/bin/edged/src/api/dataset/add.rs b/copperd/bin/edged/src/api/dataset/add.rs
index 4080865e..6b253ed3 100644
--- a/copperd/bin/edged/src/api/dataset/add.rs
+++ b/copperd/bin/edged/src/api/dataset/add.rs
@@ -6,8 +6,9 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::{client::ItemdbClient, errors::dataset::AddDatasetError};
+use copper_itemdb::client::errors::dataset::AddDatasetError;
 use serde::Deserialize;
+use sqlx::Acquire;
 use tracing::error;
 use utoipa::ToSchema;
 
@@ -28,9 +29,9 @@ pub(super) struct NewDatasetRequest {
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn add_dataset<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn add_dataset<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Json(payload): Json<NewDatasetRequest>,
 ) -> Response {
 	let user = match state.auth.auth_or_logout(&state, &jar).await {
@@ -38,13 +39,51 @@ pub(super) async fn add_dataset<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		Ok(user) => user,
 	};
 
+	let mut conn = match state.itemdb_client.new_connection().await {
+		Ok(x) => x,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let mut trans = match conn.begin().await {
+		Ok(y) => y,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
 	let res = state
 		.itemdb_client
-		.add_dataset(&payload.name, user.id)
+		.add_dataset(&mut trans, &payload.name, user.id)
 		.await;
 
 	return match res {
-		Ok(x) => (StatusCode::OK, Json(x)).into_response(),
+		Ok(x) => {
+			match trans.commit().await {
+				Ok(()) => {}
+				Err(error) => {
+					error!(message = "Error while committing transaction", ?error);
+					return (
+						StatusCode::INTERNAL_SERVER_ERROR,
+						Json("Internal server error"),
+					)
+						.into_response();
+				}
+			};
+
+			(StatusCode::OK, Json(x)).into_response()
+		}
 
 		Err(AddDatasetError::UniqueViolation) => {
 			return (
@@ -60,7 +99,11 @@ pub(super) async fn add_dataset<Client: DatabaseClient, Itemdb: ItemdbClient>(
 
 		Err(AddDatasetError::DbError(error)) => {
 			error!(message = "Error in itemdb client", ?error);
-			return (StatusCode::INTERNAL_SERVER_ERROR, Json("Internal server error")).into_response();
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
 		}
 	};
 }
diff --git a/copperd/bin/edged/src/api/dataset/add_class.rs b/copperd/bin/edged/src/api/dataset/add_class.rs
index 6bf1b348..7133c172 100644
--- a/copperd/bin/edged/src/api/dataset/add_class.rs
+++ b/copperd/bin/edged/src/api/dataset/add_class.rs
@@ -6,11 +6,9 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::{
-	client::ItemdbClient,
-	errors::{class::AddClassError, dataset::GetDatasetError},
-};
+use copper_itemdb::client::errors::{class::AddClassError, dataset::GetDatasetError};
 use serde::{Deserialize, Serialize};
+use sqlx::Acquire;
 use tracing::error;
 use utoipa::ToSchema;
 
@@ -35,9 +33,9 @@ pub(super) struct NewClassRequest {
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn add_class<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn add_class<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(dataset_id): Path<i64>,
 	Json(payload): Json<NewClassRequest>,
 ) -> Response {
@@ -46,7 +44,35 @@ pub(super) async fn add_class<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		Ok(user) => user,
 	};
 
-	match state.itemdb_client.get_dataset(dataset_id.into()).await {
+	let mut conn = match state.itemdb_client.new_connection().await {
+		Ok(x) => x,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let mut trans = match conn.begin().await {
+		Ok(y) => y,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	match state
+		.itemdb_client
+		.get_dataset(&mut trans, dataset_id.into())
+		.await
+	{
 		Ok(x) => {
 			// We can only modify our own datasets
 			if x.owner != user.id {
@@ -70,11 +96,25 @@ pub(super) async fn add_class<Client: DatabaseClient, Itemdb: ItemdbClient>(
 
 	let res = state
 		.itemdb_client
-		.add_class(dataset_id.into(), &payload.name)
+		.add_class(&mut trans, dataset_id.into(), &payload.name)
 		.await;
 
 	return match res {
-		Ok(x) => (StatusCode::OK, Json(x)).into_response(),
+		Ok(x) => {
+			match trans.commit().await {
+				Ok(()) => {}
+				Err(error) => {
+					error!(message = "Error while committing transaction", ?error);
+					return (
+						StatusCode::INTERNAL_SERVER_ERROR,
+						Json("Internal server error"),
+					)
+						.into_response();
+				}
+			};
+
+			(StatusCode::OK, Json(x)).into_response()
+		}
 
 		Err(AddClassError::UniqueViolation) => {
 			return (
diff --git a/copperd/bin/edged/src/api/dataset/del.rs b/copperd/bin/edged/src/api/dataset/del.rs
index b5757208..ddc1a82e 100644
--- a/copperd/bin/edged/src/api/dataset/del.rs
+++ b/copperd/bin/edged/src/api/dataset/del.rs
@@ -6,10 +6,8 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::{
-	client::ItemdbClient,
-	errors::dataset::{DeleteDatasetError, GetDatasetError},
-};
+use copper_itemdb::client::errors::dataset::{DeleteDatasetError, GetDatasetError};
+use sqlx::Acquire;
 use tracing::error;
 
 use crate::api::RouterState;
@@ -26,9 +24,9 @@ use crate::api::RouterState;
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn del_dataset<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn del_dataset<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(dataset_id): Path<i64>,
 ) -> Response {
 	let user = match state.auth.auth_or_logout(&state, &jar).await {
@@ -36,7 +34,35 @@ pub(super) async fn del_dataset<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		Ok(user) => user,
 	};
 
-	match state.itemdb_client.get_dataset(dataset_id.into()).await {
+	let mut conn = match state.itemdb_client.new_connection().await {
+		Ok(x) => x,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let mut trans = match conn.begin().await {
+		Ok(y) => y,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	match state
+		.itemdb_client
+		.get_dataset(&mut trans, dataset_id.into())
+		.await
+	{
 		Ok(x) => {
 			// We can only modify our own datasets
 			if x.owner != user.id {
@@ -58,10 +84,23 @@ pub(super) async fn del_dataset<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		}
 	};
 
-	let res = state.itemdb_client.del_dataset(dataset_id.into()).await;
+	let res = state
+		.itemdb_client
+		.del_dataset(&mut trans, dataset_id.into())
+		.await;
 
 	return match res {
-		Ok(()) => StatusCode::OK.into_response(),
+		Ok(()) => match trans.commit().await {
+			Ok(()) => StatusCode::OK.into_response(),
+			Err(error) => {
+				error!(message = "Error while committing transaction", ?error);
+				return (
+					StatusCode::INTERNAL_SERVER_ERROR,
+					Json("Internal server error"),
+				)
+					.into_response();
+			}
+		},
 
 		Err(DeleteDatasetError::DbError(error)) => {
 			error!(message = "Error in itemdb client", ?error);
diff --git a/copperd/bin/edged/src/api/dataset/get.rs b/copperd/bin/edged/src/api/dataset/get.rs
index cf54c388..0e6255fd 100644
--- a/copperd/bin/edged/src/api/dataset/get.rs
+++ b/copperd/bin/edged/src/api/dataset/get.rs
@@ -7,7 +7,8 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::{client::ItemdbClient, errors::dataset::GetDatasetError};
+use copper_itemdb::client::errors::dataset::GetDatasetError;
+use sqlx::Acquire;
 use tracing::error;
 
 /// Get dataset info
@@ -24,9 +25,9 @@ use tracing::error;
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn get_dataset<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn get_dataset<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(dataset_id): Path<i64>,
 ) -> Response {
 	let user = match state.auth.auth_or_logout(&state, &jar).await {
@@ -34,7 +35,35 @@ pub(super) async fn get_dataset<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		Ok(user) => user,
 	};
 
-	return match state.itemdb_client.get_dataset(dataset_id.into()).await {
+	let mut conn = match state.itemdb_client.new_connection().await {
+		Ok(x) => x,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let mut trans = match conn.begin().await {
+		Ok(y) => y,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	return match state
+		.itemdb_client
+		.get_dataset(&mut trans, dataset_id.into())
+		.await
+	{
 		Ok(x) => {
 			if x.owner != user.id {
 				return (StatusCode::UNAUTHORIZED, Json("Unauthorized")).into_response();
diff --git a/copperd/bin/edged/src/api/dataset/list.rs b/copperd/bin/edged/src/api/dataset/list.rs
index a2e7351c..f078781e 100644
--- a/copperd/bin/edged/src/api/dataset/list.rs
+++ b/copperd/bin/edged/src/api/dataset/list.rs
@@ -7,7 +7,8 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::{client::ItemdbClient, errors::dataset::ListDatasetsError};
+use copper_itemdb::client::errors::dataset::ListDatasetsError;
+use sqlx::Acquire;
 use tracing::error;
 
 /// Get dataset info
@@ -19,21 +20,49 @@ use tracing::error;
 		(status = 500, description = "Internal server error"),
 	),
 )]
-pub(super) async fn list_datasets<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn list_datasets<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 ) -> Response {
 	let user = match state.auth.auth_or_logout(&state, &jar).await {
 		Err(x) => return x,
 		Ok(user) => user,
 	};
 
-	return match state.itemdb_client.list_datasets(user.id).await {
+	let mut conn = match state.itemdb_client.new_connection().await {
+		Ok(x) => x,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let mut trans = match conn.begin().await {
+		Ok(y) => y,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	return match state.itemdb_client.list_datasets(&mut trans, user.id).await {
 		Ok(x) => (StatusCode::OK, Json(x)).into_response(),
 
 		Err(ListDatasetsError::DbError(error)) => {
 			error!(message = "Error in itemdb client", ?error);
-			return (StatusCode::INTERNAL_SERVER_ERROR, Json("Internal server error")).into_response();
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
 		}
 	};
 }
diff --git a/copperd/bin/edged/src/api/dataset/mod.rs b/copperd/bin/edged/src/api/dataset/mod.rs
index efd4894e..6e656b9e 100644
--- a/copperd/bin/edged/src/api/dataset/mod.rs
+++ b/copperd/bin/edged/src/api/dataset/mod.rs
@@ -4,7 +4,6 @@ use axum::{
 	routing::{delete, get, patch, post},
 	Router,
 };
-use copper_itemdb::client::base::client::ItemdbClient;
 use utoipa::OpenApi;
 
 mod add;
@@ -36,8 +35,7 @@ use rename::*;
 )]
 pub(super) struct DatasetApi;
 
-pub(super) fn router<Client: DatabaseClient + 'static, Itemdb: ItemdbClient + 'static>(
-) -> Router<RouterState<Client, Itemdb>> {
+pub(super) fn router<Client: DatabaseClient + 'static>() -> Router<RouterState<Client>> {
 	Router::new()
 		.route("/", post(add_dataset))
 		.route("/:dataset_id", get(get_dataset))
diff --git a/copperd/bin/edged/src/api/dataset/rename.rs b/copperd/bin/edged/src/api/dataset/rename.rs
index 4d60d13a..2aed99f9 100644
--- a/copperd/bin/edged/src/api/dataset/rename.rs
+++ b/copperd/bin/edged/src/api/dataset/rename.rs
@@ -6,11 +6,9 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::{
-	client::ItemdbClient,
-	errors::dataset::{GetDatasetError, RenameDatasetError},
-};
+use copper_itemdb::client::errors::dataset::{GetDatasetError, RenameDatasetError};
 use serde::Deserialize;
+use sqlx::Acquire;
 use tracing::error;
 use utoipa::ToSchema;
 
@@ -35,9 +33,9 @@ pub(super) struct RenameDatasetRequest {
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn rename_dataset<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn rename_dataset<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(dataset_id): Path<i64>,
 	Json(payload): Json<RenameDatasetRequest>,
 ) -> Response {
@@ -46,7 +44,35 @@ pub(super) async fn rename_dataset<Client: DatabaseClient, Itemdb: ItemdbClient>
 		Ok(user) => user,
 	};
 
-	match state.itemdb_client.get_dataset(dataset_id.into()).await {
+	let mut conn = match state.itemdb_client.new_connection().await {
+		Ok(x) => x,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let mut trans = match conn.begin().await {
+		Ok(y) => y,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	match state
+		.itemdb_client
+		.get_dataset(&mut trans, dataset_id.into())
+		.await
+	{
 		Ok(x) => {
 			// We can only modify our own datasets
 			if x.owner != user.id {
@@ -70,11 +96,21 @@ pub(super) async fn rename_dataset<Client: DatabaseClient, Itemdb: ItemdbClient>
 
 	let res = state
 		.itemdb_client
-		.rename_dataset(dataset_id.into(), &payload.new_name)
+		.rename_dataset(&mut trans, dataset_id.into(), &payload.new_name)
 		.await;
 
 	return match res {
-		Ok(()) => StatusCode::OK.into_response(),
+		Ok(()) => match trans.commit().await {
+			Ok(()) => StatusCode::OK.into_response(),
+			Err(error) => {
+				error!(message = "Error while committing transaction", ?error);
+				return (
+					StatusCode::INTERNAL_SERVER_ERROR,
+					Json("Internal server error"),
+				)
+					.into_response();
+			}
+		},
 
 		Err(RenameDatasetError::UniqueViolation) => {
 			return (
diff --git a/copperd/bin/edged/src/api/item/attr.rs b/copperd/bin/edged/src/api/item/attr.rs
index 4be178dd..5ea01a11 100644
--- a/copperd/bin/edged/src/api/item/attr.rs
+++ b/copperd/bin/edged/src/api/item/attr.rs
@@ -8,12 +8,10 @@ use axum::{
 };
 use axum_extra::{body::AsyncReadBody, extract::CookieJar};
 use copper_itemdb::{
-	client::base::{
-		client::ItemdbClient,
-		errors::{class::GetClassError, dataset::GetDatasetError, item::GetItemError},
-	},
+	client::errors::{class::GetClassError, dataset::GetDatasetError, item::GetItemError},
 	AttrData, AttributeId,
 };
+use sqlx::Acquire;
 use tracing::error;
 
 /// Get the value of an item's attribute
@@ -29,9 +27,9 @@ use tracing::error;
 		(status = 500, description = "Internal server error"),
 	),
 )]
-pub(super) async fn get_attr<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn get_attr<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path((item_id, attr_id)): Path<(i64, i64)>,
 ) -> Response {
 	let attr_id: AttributeId = attr_id.into();
@@ -40,7 +38,35 @@ pub(super) async fn get_attr<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		Ok(user) => user,
 	};
 
-	let item = match state.itemdb_client.get_item(item_id.into()).await {
+	let mut conn = match state.itemdb_client.new_connection().await {
+		Ok(x) => x,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let mut trans = match conn.begin().await {
+		Ok(y) => y,
+		Err(error) => {
+			error!(message = "Error in itemdb client", ?error);
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
+		}
+	};
+
+	let item = match state
+		.itemdb_client
+		.get_item(&mut trans, item_id.into())
+		.await
+	{
 		Ok(x) => x,
 
 		Err(GetItemError::NotFound) => {
@@ -58,7 +84,7 @@ pub(super) async fn get_attr<Client: DatabaseClient, Itemdb: ItemdbClient>(
 	};
 
 	// TODO: do permission checks in one query
-	let class = match state.itemdb_client.get_class(item.class).await {
+	let class = match state.itemdb_client.get_class(&mut trans, item.class).await {
 		Ok(x) => x,
 
 		Err(GetClassError::NotFound) => return StatusCode::NOT_FOUND.into_response(),
@@ -73,7 +99,11 @@ pub(super) async fn get_attr<Client: DatabaseClient, Itemdb: ItemdbClient>(
 		}
 	};
 
-	match state.itemdb_client.get_dataset(class.dataset).await {
+	match state
+		.itemdb_client
+		.get_dataset(&mut trans, class.dataset)
+		.await
+	{
 		Ok(x) => {
 			if x.owner != user.id {
 				return (StatusCode::UNAUTHORIZED, Json("Unauthorized")).into_response();
diff --git a/copperd/bin/edged/src/api/item/mod.rs b/copperd/bin/edged/src/api/item/mod.rs
index f183761f..7e27be46 100644
--- a/copperd/bin/edged/src/api/item/mod.rs
+++ b/copperd/bin/edged/src/api/item/mod.rs
@@ -2,7 +2,6 @@ use crate::database::base::client::DatabaseClient;
 use crate::RouterState;
 use axum::routing::get;
 use axum::Router;
-use copper_itemdb::client::base::client::ItemdbClient;
 use utoipa::OpenApi;
 
 mod attr;
@@ -13,7 +12,6 @@ use attr::*;
 #[openapi(tags(), paths(get_attr), components(schemas()))]
 pub(super) struct ItemApi;
 
-pub(super) fn router<Client: DatabaseClient + 'static, Itemdb: ItemdbClient + 'static>(
-) -> Router<RouterState<Client, Itemdb>> {
+pub(super) fn router<Client: DatabaseClient + 'static>() -> Router<RouterState<Client>> {
 	Router::new().route("/:item_idx/attr/:attr_idx", get(get_attr))
 }
diff --git a/copperd/bin/edged/src/api/job/list.rs b/copperd/bin/edged/src/api/job/list.rs
index 63ceb863..27ef4c36 100644
--- a/copperd/bin/edged/src/api/job/list.rs
+++ b/copperd/bin/edged/src/api/job/list.rs
@@ -8,7 +8,6 @@ use axum::{
 	response::{IntoResponse, Response},
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::client::ItemdbClient;
 use copper_jobqueue::base::errors::GetUserJobsError;
 use serde::Deserialize;
 use tracing::error;
@@ -33,9 +32,9 @@ pub(super) struct PaginateParams {
 		("bearer" = []),
 	)
 )]
-pub(super) async fn list_jobs<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn list_jobs<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Query(paginate): Query<PaginateParams>,
 ) -> Response {
 	let user = match state.auth.auth_or_logout(&state, &jar).await {
@@ -52,7 +51,11 @@ pub(super) async fn list_jobs<Client: DatabaseClient, Itemdb: ItemdbClient>(
 
 		Err(GetUserJobsError::DbError(error)) => {
 			error!(message = "Error while getting user jobs", ?error, ?user);
-			return (StatusCode::INTERNAL_SERVER_ERROR, Json("Internal server error")).into_response();
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
 		}
 	};
 }
diff --git a/copperd/bin/edged/src/api/job/mod.rs b/copperd/bin/edged/src/api/job/mod.rs
index ca62c1d2..242bcba9 100644
--- a/copperd/bin/edged/src/api/job/mod.rs
+++ b/copperd/bin/edged/src/api/job/mod.rs
@@ -1,7 +1,6 @@
 use crate::database::base::client::DatabaseClient;
 use crate::RouterState;
 use axum::{routing::get, Router};
-use copper_itemdb::client::base::client::ItemdbClient;
 use copper_jobqueue::info::{QueuedJobInfoList, QueuedJobInfoShort, QueuedJobState};
 use utoipa::OpenApi;
 
@@ -18,7 +17,6 @@ use list::*;
 )]
 pub(super) struct JobApi;
 
-pub(super) fn router<Client: DatabaseClient + 'static, Itemdb: ItemdbClient + 'static>(
-) -> Router<RouterState<Client, Itemdb>> {
+pub(super) fn router<Client: DatabaseClient + 'static>() -> Router<RouterState<Client>> {
 	Router::new().route("/list", get(list_jobs))
 }
diff --git a/copperd/bin/edged/src/api/login.rs b/copperd/bin/edged/src/api/login.rs
index b10ba16e..1c77a806 100644
--- a/copperd/bin/edged/src/api/login.rs
+++ b/copperd/bin/edged/src/api/login.rs
@@ -5,7 +5,6 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::cookie::{Cookie, SameSite};
-use copper_itemdb::client::base::client::ItemdbClient;
 use serde::Deserialize;
 use tracing::{error, info};
 use utoipa::ToSchema;
@@ -30,9 +29,9 @@ pub(super) struct LoginRequest {
 		(status = 500, description = "Internal server error", body=String),
 	),
 )]
-pub(super) async fn try_login<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn try_login<Client: DatabaseClient>(
 	ConnectInfo(connect_info): ConnectInfo<CopperConnectInfo>,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Json(payload): Json<LoginRequest>,
 ) -> Response {
 	info!(
diff --git a/copperd/bin/edged/src/api/logout.rs b/copperd/bin/edged/src/api/logout.rs
index d972a222..6db7ed3b 100644
--- a/copperd/bin/edged/src/api/logout.rs
+++ b/copperd/bin/edged/src/api/logout.rs
@@ -8,7 +8,6 @@ use axum_extra::extract::{
 	cookie::{Cookie, Expiration, SameSite},
 	CookieJar,
 };
-use copper_itemdb::client::base::client::ItemdbClient;
 use time::OffsetDateTime;
 use tracing::info;
 
@@ -25,9 +24,9 @@ use crate::{auth::AUTH_COOKIE_NAME, database::base::client::DatabaseClient};
 		(status = 500, description = "Internal server error", body = String),
 	),
 )]
-pub(super) async fn logout<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn logout<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 ) -> Response {
 	info!(message = "Received logout request", cookies = ?jar);
 
diff --git a/copperd/bin/edged/src/api/mod.rs b/copperd/bin/edged/src/api/mod.rs
index a8e88f42..19702d07 100644
--- a/copperd/bin/edged/src/api/mod.rs
+++ b/copperd/bin/edged/src/api/mod.rs
@@ -3,7 +3,7 @@ use axum::routing::post;
 use axum::serve::IncomingStream;
 use axum::{extract::DefaultBodyLimit, Router};
 use copper_edged::UserInfo;
-use copper_itemdb::client::base::client::ItemdbClient;
+use copper_itemdb::client::ItemdbClient;
 use copper_itemdb::{AttrDataStub, AttributeInfo, AttributeOptions, ClassInfo, DatasetInfo};
 use copper_jobqueue::base::client::JobQueueClient;
 use copper_jobqueue::info::QueuedJobCounts;
@@ -49,10 +49,10 @@ impl Connected<IncomingStream<'_>> for CopperConnectInfo {
 	}
 }
 
-pub struct RouterState<Client: DatabaseClient, Itemdb: ItemdbClient> {
+pub struct RouterState<Client: DatabaseClient> {
 	pub config: Arc<EdgedConfig>,
 	pub db_client: Arc<Client>,
-	pub itemdb_client: Arc<Itemdb>,
+	pub itemdb_client: Arc<ItemdbClient>,
 	pub jobqueue_client: Arc<dyn JobQueueClient>,
 	pub auth: Arc<AuthHelper<Client>>,
 	pub s3_client: Arc<S3Client>,
@@ -61,7 +61,7 @@ pub struct RouterState<Client: DatabaseClient, Itemdb: ItemdbClient> {
 
 // We need to impl this manually, since `DatabaseClient`
 // doesn't implement `Clone`
-impl<Client: DatabaseClient, Itemdb: ItemdbClient> Clone for RouterState<Client, Itemdb> {
+impl<Client: DatabaseClient> Clone for RouterState<Client> {
 	fn clone(&self) -> Self {
 		Self {
 			config: self.config.clone(),
@@ -96,9 +96,7 @@ impl<Client: DatabaseClient, Itemdb: ItemdbClient> Clone for RouterState<Client,
 )]
 struct ApiDoc;
 
-pub(super) fn router<Client: DatabaseClient + 'static, Itemdb: ItemdbClient + 'static>(
-	state: RouterState<Client, Itemdb>,
-) -> Router {
+pub(super) fn router<Client: DatabaseClient + 'static>(state: RouterState<Client>) -> Router {
 	Router::new()
 		.merge(SwaggerUi::new("/docs").url("/docs/openapi.json", ApiDoc::openapi()))
 		//
diff --git a/copperd/bin/edged/src/api/pipeline/add.rs b/copperd/bin/edged/src/api/pipeline/add.rs
index a034e89c..6c409b6b 100644
--- a/copperd/bin/edged/src/api/pipeline/add.rs
+++ b/copperd/bin/edged/src/api/pipeline/add.rs
@@ -6,7 +6,6 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::client::ItemdbClient;
 use copper_piper::json::PipelineJson;
 use serde::Deserialize;
 use tracing::error;
@@ -34,10 +33,10 @@ pub(super) struct NewPipelineRequest {
 		("bearer" = []),
 	)
 )]
-pub(super) async fn add_pipeline<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn add_pipeline<Client: DatabaseClient>(
 	// OriginalUri(uri): OriginalUri,
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Json(payload): Json<NewPipelineRequest>,
 ) -> Response {
 	let user = match state.auth.auth_or_logout(&state, &jar).await {
diff --git a/copperd/bin/edged/src/api/pipeline/del.rs b/copperd/bin/edged/src/api/pipeline/del.rs
index 9280c117..20aa85c9 100644
--- a/copperd/bin/edged/src/api/pipeline/del.rs
+++ b/copperd/bin/edged/src/api/pipeline/del.rs
@@ -9,7 +9,6 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::client::ItemdbClient;
 use tracing::error;
 
 use crate::api::RouterState;
@@ -27,10 +26,10 @@ use crate::api::RouterState;
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn del_pipeline<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn del_pipeline<Client: DatabaseClient>(
 	// OriginalUri(uri): OriginalUri,
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(pipeline_id): Path<i64>,
 ) -> Response {
 	let user = match state.auth.auth_or_logout(&state, &jar).await {
diff --git a/copperd/bin/edged/src/api/pipeline/get.rs b/copperd/bin/edged/src/api/pipeline/get.rs
index 0a23f131..25409514 100644
--- a/copperd/bin/edged/src/api/pipeline/get.rs
+++ b/copperd/bin/edged/src/api/pipeline/get.rs
@@ -7,7 +7,6 @@ use axum::{
 	response::{IntoResponse, Response},
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::client::ItemdbClient;
 use tracing::error;
 
 /// Get pipeline by id
@@ -23,10 +22,10 @@ use tracing::error;
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn get_pipeline<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn get_pipeline<Client: DatabaseClient>(
 	// OriginalUri(uri): OriginalUri,
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(pipeline_id): Path<i64>,
 ) -> Response {
 	let user = match state.auth.auth_or_logout(&state, &jar).await {
diff --git a/copperd/bin/edged/src/api/pipeline/list.rs b/copperd/bin/edged/src/api/pipeline/list.rs
index a2d18a14..a66ed181 100644
--- a/copperd/bin/edged/src/api/pipeline/list.rs
+++ b/copperd/bin/edged/src/api/pipeline/list.rs
@@ -8,7 +8,6 @@ use axum::{
 	response::{IntoResponse, Response},
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::client::ItemdbClient;
 use tracing::error;
 
 /// List the logged in user's pipelines
@@ -21,9 +20,9 @@ use tracing::error;
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn list_pipelines<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn list_pipelines<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 ) -> Response {
 	let user = match state.auth.auth_or_logout(&state, &jar).await {
 		Err(x) => return x,
@@ -38,7 +37,11 @@ pub(super) async fn list_pipelines<Client: DatabaseClient, Itemdb: ItemdbClient>
 				user_id = ?user.id,
 				?error,
 			);
-			return (StatusCode::INTERNAL_SERVER_ERROR, Json("Internal server error")).into_response();
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
 		}
 	};
 }
diff --git a/copperd/bin/edged/src/api/pipeline/mod.rs b/copperd/bin/edged/src/api/pipeline/mod.rs
index 0fddabf4..f30df6e6 100644
--- a/copperd/bin/edged/src/api/pipeline/mod.rs
+++ b/copperd/bin/edged/src/api/pipeline/mod.rs
@@ -5,7 +5,6 @@ use axum::{
 	Router,
 };
 use copper_edged::PipelineInfo;
-use copper_itemdb::client::base::client::ItemdbClient;
 use copper_piper::{
 	base::NodeParameterValue,
 	json::{EdgeJson, InputPort, NodeJson, NodeJsonPosition, OutputPort, PipelineJson},
@@ -55,8 +54,7 @@ use update::*;
 )]
 pub(super) struct PipelineApi;
 
-pub(super) fn router<Client: DatabaseClient + 'static, Itemdb: ItemdbClient + 'static>(
-) -> Router<RouterState<Client, Itemdb>> {
+pub(super) fn router<Client: DatabaseClient + 'static>() -> Router<RouterState<Client>> {
 	Router::new()
 		.route("/", post(add_pipeline))
 		.route("/list", get(list_pipelines))
diff --git a/copperd/bin/edged/src/api/pipeline/run.rs b/copperd/bin/edged/src/api/pipeline/run.rs
index c4e7caa1..86486b94 100644
--- a/copperd/bin/edged/src/api/pipeline/run.rs
+++ b/copperd/bin/edged/src/api/pipeline/run.rs
@@ -5,7 +5,7 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::{client::base::client::ItemdbClient, AttrData, ClassId, ItemId};
+use copper_itemdb::{AttrData, ClassId, ItemId};
 use copper_jobqueue::base::errors::AddJobError;
 use copper_util::HashType;
 use serde::Deserialize;
@@ -151,9 +151,9 @@ pub(super) struct RunPipelineRequest {
 		("bearer" = []),
 	)
 )]
-pub(super) async fn run_pipeline<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn run_pipeline<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(pipeline_id): Path<i64>,
 	Json(payload): Json<RunPipelineRequest>,
 ) -> Response {
@@ -171,7 +171,11 @@ pub(super) async fn run_pipeline<Client: DatabaseClient, Itemdb: ItemdbClient>(
 				?pipeline_id,
 				?error,
 			);
-			return (StatusCode::INTERNAL_SERVER_ERROR, Json("Internal server error")).into_response();
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
 		}
 	};
 
@@ -267,7 +271,11 @@ pub(super) async fn run_pipeline<Client: DatabaseClient, Itemdb: ItemdbClient>(
 
 		Err(AddJobError::DbError(error)) => {
 			error!(message = "DB error while queueing job", ?error, ?payload.job_id);
-			return (StatusCode::INTERNAL_SERVER_ERROR, Json("Internal server error")).into_response();
+			return (
+				StatusCode::INTERNAL_SERVER_ERROR,
+				Json("Internal server error"),
+			)
+				.into_response();
 		}
 
 		Err(AddJobError::AlreadyExists) => {
diff --git a/copperd/bin/edged/src/api/pipeline/update.rs b/copperd/bin/edged/src/api/pipeline/update.rs
index 5ac92c0f..58dc3bf7 100644
--- a/copperd/bin/edged/src/api/pipeline/update.rs
+++ b/copperd/bin/edged/src/api/pipeline/update.rs
@@ -9,7 +9,6 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::client::ItemdbClient;
 use copper_piper::json::PipelineJson;
 use serde::Deserialize;
 use tracing::error;
@@ -37,10 +36,10 @@ pub(super) struct UpdatePipelineRequest {
 		(status = 500, description = "Internal server error"),
 	),
 )]
-pub(super) async fn update_pipeline<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn update_pipeline<Client: DatabaseClient>(
 	// OriginalUri(uri): OriginalUri,
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(pipeline_id): Path<i64>,
 	Json(payload): Json<UpdatePipelineRequest>,
 ) -> Response {
diff --git a/copperd/bin/edged/src/api/storage/finish_upload.rs b/copperd/bin/edged/src/api/storage/finish_upload.rs
index 0b8aa789..5c86a7f9 100644
--- a/copperd/bin/edged/src/api/storage/finish_upload.rs
+++ b/copperd/bin/edged/src/api/storage/finish_upload.rs
@@ -5,7 +5,6 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::client::ItemdbClient;
 use tracing::error;
 
 use crate::{api::RouterState, uploader::errors::UploadFinishError};
@@ -26,9 +25,9 @@ use crate::{database::base::client::DatabaseClient, uploader::UploadJobId};
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn finish_upload<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn finish_upload<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(job_id): Path<UploadJobId>,
 ) -> Response {
 	let user = match state.auth.auth_or_logout(&state, &jar).await {
diff --git a/copperd/bin/edged/src/api/storage/mod.rs b/copperd/bin/edged/src/api/storage/mod.rs
index 7c97a868..122ecb38 100644
--- a/copperd/bin/edged/src/api/storage/mod.rs
+++ b/copperd/bin/edged/src/api/storage/mod.rs
@@ -1,7 +1,6 @@
 use crate::database::base::client::DatabaseClient;
 use crate::RouterState;
 use axum::{routing::post, Router};
-use copper_itemdb::client::base::client::ItemdbClient;
 use utoipa::OpenApi;
 
 mod finish_upload;
@@ -20,8 +19,7 @@ use upload_part::*;
 )]
 pub(super) struct StorageApi;
 
-pub(super) fn router<Client: DatabaseClient + 'static, Itemdb: ItemdbClient + 'static>(
-) -> Router<RouterState<Client, Itemdb>> {
+pub(super) fn router<Client: DatabaseClient + 'static>() -> Router<RouterState<Client>> {
 	Router::new()
 		.route("/upload", post(start_upload))
 		.route("/upload/:upload_id/part", post(upload_part))
diff --git a/copperd/bin/edged/src/api/storage/start_upload.rs b/copperd/bin/edged/src/api/storage/start_upload.rs
index 8df68615..29e85b27 100644
--- a/copperd/bin/edged/src/api/storage/start_upload.rs
+++ b/copperd/bin/edged/src/api/storage/start_upload.rs
@@ -5,7 +5,6 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::client::ItemdbClient;
 use copper_util::MimeType;
 use serde::{Deserialize, Serialize};
 use tracing::error;
@@ -37,9 +36,9 @@ pub(super) struct StartUploadResponse {
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn start_upload<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn start_upload<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Json(payload): Json<StartUploadRequest>,
 ) -> Response {
 	let user = match state.auth.auth_or_logout(&state, &jar).await {
diff --git a/copperd/bin/edged/src/api/storage/upload_part.rs b/copperd/bin/edged/src/api/storage/upload_part.rs
index b1f8dd41..ea9cacda 100644
--- a/copperd/bin/edged/src/api/storage/upload_part.rs
+++ b/copperd/bin/edged/src/api/storage/upload_part.rs
@@ -6,7 +6,6 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::client::ItemdbClient;
 use tracing::{error, warn};
 
 use crate::{api::RouterState, uploader::errors::UploadFragmentError};
@@ -28,9 +27,9 @@ use crate::{database::base::client::DatabaseClient, uploader::UploadJobId};
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn upload_part<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn upload_part<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(job_id): Path<UploadJobId>,
 	mut multipart: Multipart,
 ) -> Response {
diff --git a/copperd/bin/edged/src/api/user/add.rs b/copperd/bin/edged/src/api/user/add.rs
index de89f3c6..62145c21 100644
--- a/copperd/bin/edged/src/api/user/add.rs
+++ b/copperd/bin/edged/src/api/user/add.rs
@@ -6,7 +6,6 @@ use axum::{
 	Json,
 };
 use copper_edged::UserPassword;
-use copper_itemdb::client::base::client::ItemdbClient;
 use serde::{Deserialize, Serialize};
 use tracing::error;
 use utoipa::ToSchema;
@@ -31,8 +30,8 @@ pub(super) struct NewUserRequest {
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn add_user<Client: DatabaseClient, Itemdb: ItemdbClient>(
-	State(state): State<RouterState<Client, Itemdb>>,
+pub(super) async fn add_user<Client: DatabaseClient>(
+	State(state): State<RouterState<Client>>,
 	Json(payload): Json<NewUserRequest>,
 ) -> Response {
 	let password = UserPassword::new(&payload.password);
diff --git a/copperd/bin/edged/src/api/user/del.rs b/copperd/bin/edged/src/api/user/del.rs
index 75e67f38..f046b504 100644
--- a/copperd/bin/edged/src/api/user/del.rs
+++ b/copperd/bin/edged/src/api/user/del.rs
@@ -6,7 +6,6 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::client::ItemdbClient;
 use tracing::error;
 
 use crate::api::RouterState;
@@ -24,10 +23,10 @@ use crate::api::RouterState;
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn del_user<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn del_user<Client: DatabaseClient>(
 	// OriginalUri(uri): OriginalUri,
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(user_id): Path<i64>,
 ) -> Response {
 	let user = match state.auth.auth_or_logout(&state, &jar).await {
diff --git a/copperd/bin/edged/src/api/user/me.rs b/copperd/bin/edged/src/api/user/me.rs
index 8d8a9cf6..57082322 100644
--- a/copperd/bin/edged/src/api/user/me.rs
+++ b/copperd/bin/edged/src/api/user/me.rs
@@ -7,7 +7,6 @@ use axum::{
 	Json,
 };
 use axum_extra::extract::CookieJar;
-use copper_itemdb::client::base::client::ItemdbClient;
 
 /// Get logged in user info
 #[utoipa::path(
@@ -19,9 +18,9 @@ use copper_itemdb::client::base::client::ItemdbClient;
 		(status = 500, description = "Internal server error"),
 	)
 )]
-pub(super) async fn get_me<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn get_me<Client: DatabaseClient>(
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 ) -> Response {
 	match state.auth.auth_or_logout(&state, &jar).await {
 		Err(response) => response,
diff --git a/copperd/bin/edged/src/api/user/mod.rs b/copperd/bin/edged/src/api/user/mod.rs
index 65b3f81a..ce7cbec6 100644
--- a/copperd/bin/edged/src/api/user/mod.rs
+++ b/copperd/bin/edged/src/api/user/mod.rs
@@ -4,7 +4,6 @@ use axum::{
 	routing::{delete, get, patch, post},
 	Router,
 };
-use copper_itemdb::client::base::client::ItemdbClient;
 use utoipa::OpenApi;
 
 mod add;
@@ -25,8 +24,7 @@ use update::*;
 )]
 pub(super) struct UserApi;
 
-pub(super) fn router<Client: DatabaseClient + 'static, Itemdb: ItemdbClient + 'static>(
-) -> Router<RouterState<Client, Itemdb>> {
+pub(super) fn router<Client: DatabaseClient + 'static>() -> Router<RouterState<Client>> {
 	Router::new()
 		.route("/", post(add_user))
 		.route("/me", get(get_me))
diff --git a/copperd/bin/edged/src/api/user/update.rs b/copperd/bin/edged/src/api/user/update.rs
index a9b17878..90612fb5 100644
--- a/copperd/bin/edged/src/api/user/update.rs
+++ b/copperd/bin/edged/src/api/user/update.rs
@@ -7,7 +7,6 @@ use axum::{
 };
 use axum_extra::extract::CookieJar;
 use copper_edged::UserPassword;
-use copper_itemdb::client::base::client::ItemdbClient;
 use serde::Deserialize;
 use tracing::error;
 use utoipa::ToSchema;
@@ -35,10 +34,10 @@ pub(super) struct UpdateUserRequest {
 		(status = 500, description = "Internal server error"),
 	),
 )]
-pub(super) async fn update_user<Client: DatabaseClient, Itemdb: ItemdbClient>(
+pub(super) async fn update_user<Client: DatabaseClient>(
 	// OriginalUri(uri): OriginalUri,
 	jar: CookieJar,
-	State(state): State<RouterState<Client, Itemdb>>,
+	State(state): State<RouterState<Client>>,
 	Path(user_id): Path<i64>,
 	Json(payload): Json<UpdateUserRequest>,
 ) -> Response {
diff --git a/copperd/bin/edged/src/auth.rs b/copperd/bin/edged/src/auth.rs
index 70c96027..1c76665e 100644
--- a/copperd/bin/edged/src/auth.rs
+++ b/copperd/bin/edged/src/auth.rs
@@ -8,7 +8,7 @@ use axum_extra::extract::{
 	CookieJar,
 };
 use copper_edged::UserInfo;
-use copper_itemdb::{client::base::client::ItemdbClient, UserId};
+use copper_itemdb::UserId;
 use rand::{distributions::Alphanumeric, Rng};
 use smartstring::{LazyCompact, SmartString};
 use std::marker::PhantomData;
@@ -93,9 +93,9 @@ impl<Client: DatabaseClient> AuthHelper<Client> {
 		}
 	}
 
-	pub async fn try_login<Itemdb: ItemdbClient>(
+	pub async fn try_login(
 		&self,
-		state: &RouterState<Client, Itemdb>,
+		state: &RouterState<Client>,
 		email: &str,
 		password: &str,
 	) -> Result<Option<AuthToken>, LoginError> {
@@ -119,9 +119,9 @@ impl<Client: DatabaseClient> AuthHelper<Client> {
 	/// Look for an authentication cookie in `jar`.
 	/// If it is there, return the logged in user's info.
 	/// If it isn't (or is invalid), return None.
-	pub async fn check_cookies<Itemdb: ItemdbClient>(
+	pub async fn check_cookies(
 		&self,
-		state: &RouterState<Client, Itemdb>,
+		state: &RouterState<Client>,
 		jar: &CookieJar,
 	) -> Result<Option<UserInfo>, GetUserError> {
 		let token = if let Some(h) = jar.get(AUTH_COOKIE_NAME) {
@@ -181,9 +181,9 @@ impl<Client: DatabaseClient> AuthHelper<Client> {
 
 	/// Match a user to an authentication token or log out.
 	/// This is a convenient wrapper around `self.check_cookies`
-	pub async fn auth_or_logout<ItemDb: ItemdbClient>(
+	pub async fn auth_or_logout(
 		&self,
-		state: &RouterState<Client, ItemDb>,
+		state: &RouterState<Client>,
 		jar: &CookieJar,
 	) -> Result<UserInfo, Response> {
 		match self.check_cookies(state, jar).await {
diff --git a/copperd/bin/edged/src/main.rs b/copperd/bin/edged/src/main.rs
index 2bca0d83..230e3192 100644
--- a/copperd/bin/edged/src/main.rs
+++ b/copperd/bin/edged/src/main.rs
@@ -5,7 +5,7 @@ use aws_sdk_s3::config::Credentials;
 use axum::Router;
 use config::EdgedConfig;
 use copper_edged::UserPassword;
-use copper_itemdb::client::postgres::{PgItemdbClient, PgItemdbOpenError};
+use copper_itemdb::client::{ItemdbClient, ItemdbOpenError};
 use copper_jobqueue::postgres::{PgJobQueueClient, PgJobQueueOpenError};
 use copper_util::{load_env, s3client::S3Client, LoadedEnv};
 use database::{
@@ -39,19 +39,19 @@ async fn make_app(config: Arc<EdgedConfig>, s3_client: Arc<S3Client>) -> Router
 
 	trace!(message = "Connecting to itemdb");
 	// Connect to database
-	let itemdb_client = match PgItemdbClient::open(&config.edged_itemdb_addr, true).await {
+	let itemdb_client = match ItemdbClient::open(&config.edged_itemdb_addr, true).await {
 		Ok(db) => Arc::new(db),
-		Err(PgItemdbOpenError::Database(e)) => {
+		Err(ItemdbOpenError::Database(e)) => {
 			error!(message = "SQL error while opening item database", err = ?e);
 			std::process::exit(1);
 		}
 
-		Err(PgItemdbOpenError::Migrate(e)) => {
+		Err(ItemdbOpenError::Migrate(e)) => {
 			error!(message = "Migration error while opening item database", err = ?e);
 			std::process::exit(1);
 		}
 
-		Err(PgItemdbOpenError::NotMigrated) => unreachable!(),
+		Err(ItemdbOpenError::NotMigrated) => unreachable!(),
 	};
 	trace!(message = "Successfully connected to itemdb");
 
diff --git a/copperd/bin/edged/src/uploader/mod.rs b/copperd/bin/edged/src/uploader/mod.rs
index 9a6a8987..07bfa19a 100644
--- a/copperd/bin/edged/src/uploader/mod.rs
+++ b/copperd/bin/edged/src/uploader/mod.rs
@@ -176,7 +176,6 @@ impl Uploader {
 
 							match info.unwrap().state {
 								QueuedJobState::FailedRunning { .. } => true,
-								QueuedJobState::FailedTransaction { .. } => true,
 								QueuedJobState::BuildError { .. } => true,
 								QueuedJobState::Success => true,
 
diff --git a/copperd/bin/piper/Cargo.toml b/copperd/bin/piper/Cargo.toml
index 28724464..c43e00ef 100644
--- a/copperd/bin/piper/Cargo.toml
+++ b/copperd/bin/piper/Cargo.toml
@@ -29,6 +29,7 @@ copper-itemdb = { workspace = true }
 nodes-audiofile = { workspace = true }
 nodes-basic = { workspace = true }
 
+sqlx = { workspace = true }
 thiserror = { workspace = true }
 aws-sdk-s3 = { workspace = true }
 aws-config = { workspace = true }
diff --git a/copperd/bin/piper/src/config.rs b/copperd/bin/piper/src/config.rs
index 21c70f96..97190107 100644
--- a/copperd/bin/piper/src/config.rs
+++ b/copperd/bin/piper/src/config.rs
@@ -35,21 +35,15 @@ pub struct PiperConfig {
 	/// Looks like `postgres://user:pass@host/database`
 	pub piper_jobqueue_addr: String,
 
-	/// The maximum size, in bytes, of a binary fragment in the pipeline.
+	/// The maximum size, in bytes, of a stream fragment in the pipeline.
 	/// Smaller values slow down pipelines; larger values use more memory.
 	#[serde(default = "PiperConfig::default_frag_size")]
-	pub piper_blob_fragment_size: usize,
+	pub piper_stream_fragment_size: usize,
 
-	/// The message capacity of binary stream channels.
-	///
-	/// Smaller values increase the probability of pipeline runs failing due to an
-	/// overflowing channel, larger values use more memory.
-	#[serde(default = "PiperConfig::default_channel_size")]
+	/// The maximum size, in bytes, of a stream processing channel.
+	/// Stream channels hold stream fragments, which contain at most `stream_fragment_size` bytes.
+	#[serde(default = "PiperConfig::default_chan_size")]
 	pub piper_stream_channel_size: usize,
-
-	/// How many pipeline jobs to run at once
-	#[serde(default = "PiperConfig::default_max_running_jobs")]
-	pub piper_max_running_jobs: usize,
 }
 
 impl PiperConfig {
@@ -57,11 +51,7 @@ impl PiperConfig {
 		10_000_000
 	}
 
-	fn default_channel_size() -> usize {
-		16
-	}
-
-	fn default_max_running_jobs() -> usize {
-		4
+	fn default_chan_size() -> usize {
+		10
 	}
 }
diff --git a/copperd/bin/piper/src/main.rs b/copperd/bin/piper/src/main.rs
index dd550099..ca5842e4 100644
--- a/copperd/bin/piper/src/main.rs
+++ b/copperd/bin/piper/src/main.rs
@@ -2,11 +2,7 @@ use aws_config::{BehaviorVersion, Region};
 use aws_sdk_s3::config::Credentials;
 use config::{PiperConfig, ASYNC_POLL_AWAIT_MS};
 use copper_itemdb::{
-	client::{
-		base::{client::ItemdbClient, errors::transaction::ApplyTransactionError},
-		postgres::{PgItemdbClient, PgItemdbOpenError},
-	},
-	transaction::Transaction,
+	client::{ItemdbClient, ItemdbOpenError},
 	AttrData,
 };
 use copper_jobqueue::{
@@ -14,14 +10,18 @@ use copper_jobqueue::{
 		client::JobQueueClient,
 		errors::{BuildErrorJobError, FailJobError, GetQueuedJobError, SuccessJobError},
 	},
+	id::QueuedJobId,
 	postgres::{PgJobQueueClient, PgJobQueueOpenError},
 };
 use copper_piper::{
-	data::{BytesSource, PipeData},
-	CopperContext, JobRunResult,
+	base::RunNodeError,
+	data::PipeData,
+	helpers::{processor::BytesProcessorBuilder, rawbytes::RawBytesSource},
+	CopperContext,
 };
 use copper_util::{load_env, s3client::S3Client, LoadedEnv};
-use pipeline::runner::{DoneJobState, PipelineRunner, StartJobError};
+use pipeline::runner::{PipelineRunner, StartJobError};
+use sqlx::Acquire;
 use std::{collections::BTreeMap, sync::Arc};
 use tokio::sync::Mutex;
 use tracing::{error, info, trace};
@@ -127,17 +127,17 @@ async fn main() {
 	trace!(message = "Connecting to itemdb");
 	// Connect to database
 	let itemdb_client = loop {
-		match PgItemdbClient::open(&config.piper_itemdb_addr, false).await {
+		match ItemdbClient::open(&config.piper_itemdb_addr, false).await {
 			Ok(db) => break Arc::new(db),
-			Err(PgItemdbOpenError::Database(e)) => {
+			Err(ItemdbOpenError::Database(e)) => {
 				error!(message = "SQL error while opening item database", err = ?e);
 				std::process::exit(1);
 			}
-			Err(PgItemdbOpenError::Migrate(e)) => {
+			Err(ItemdbOpenError::Migrate(e)) => {
 				error!(message = "Migration error while opening item database", err = ?e);
 				std::process::exit(1);
 			}
-			Err(PgItemdbOpenError::NotMigrated) => {
+			Err(ItemdbOpenError::NotMigrated) => {
 				error!(message = "Database not migrated, waiting");
 				tokio::time::sleep(std::time::Duration::from_secs(5)).await;
 			}
@@ -148,8 +148,7 @@ async fn main() {
 	//
 	// MARK: Prep runner
 	//
-	let mut runner: PipelineRunner<JobRunResult, PipeData, CopperContext<PgItemdbClient>> =
-		PipelineRunner::new();
+	let mut runner: PipelineRunner = PipelineRunner::new();
 
 	{
 		// Base nodes
@@ -184,202 +183,148 @@ async fn main() {
 	}
 
 	loop {
-		match runner.check_done_jobs().await {
-			Ok(None) => {}
+		// Run the oldest job off the queue
+		let job = match jobqueue_client.get_queued_job().await {
+			Ok(x) => x,
+			Err(GetQueuedJobError::DbError(error)) => {
+				error!(message = "DB error while getting job", ?error);
+				tokio::time::sleep(std::time::Duration::from_secs(5)).await;
+				continue;
+			}
+		};
 
-			Ok(Some(DoneJobState::Success { job_id, result })) => {
-				info!(
-					message = "Job finished successfully, processing transaction",
-					job_id = ?job_id
-				);
+		let job = if let Some(job) = job {
+			job
+		} else {
+			// No job ready, wait a bit...
+			tokio::time::sleep(std::time::Duration::from_millis(ASYNC_POLL_AWAIT_MS)).await;
+			continue;
+		};
 
-				match itemdb_client.apply_transaction(result.transaction).await {
-					Ok(()) => {
-						info!(
-							message = "Transaction processed successfully",
-							job_id = ?job_id
-						);
-
-						match jobqueue_client.success_job(&job_id).await {
-							Ok(()) => {}
-
-							Err(SuccessJobError::DbError(error)) => {
-								error!(
-									message = "DB error while marking job `Success`",
-									?job_id,
-									?error
-								);
-							}
-
-							Err(SuccessJobError::NotRunning) => {
-								error!(
-									message = "Tried to mark a job that isn't running as `Success`",
-									?job_id
-								);
-							}
-						};
-					}
-
-					Err(err) => {
-						match &err {
-							ApplyTransactionError::DbError(error) => {
-								error!(
-									message = "DB error while processing transaction",
-									?job_id,
-									?error
-								);
-							}
-
-							ApplyTransactionError::AddItemError(error) => {
-								info!(
-									message = "Failed applying pipeline transaction",
-									?job_id,
-									?error
-								)
-							}
-
-							error => {
-								info!(
-									message = "Failed applying pipeline transaction",
-									?job_id,
-									?error
-								)
-							}
-						};
-
-						match jobqueue_client
-							.fail_job_transaction(&job_id, &format!("{}", err))
-							.await
-						{
-							Ok(()) => {}
-
-							Err(FailJobError::DbError(error)) => {
-								error!(
-									message = "DB error while marking job `Failed`",
-									?job_id,
-									?error
-								);
-							}
-
-							Err(FailJobError::NotRunning) => {
-								error!(
-									message = "Tried to mark a job that isn't running as `Failed`",
-									?job_id
-								);
-							}
-						};
-					}
-				};
-			}
+		// Prepare input
+		let mut input = BTreeMap::new();
+		for (name, value) in job.input {
+			match value {
+				AttrData::Blob { bucket, key } => input.insert(
+					name,
+					PipeData::Blob {
+						source: BytesProcessorBuilder::new(RawBytesSource::S3 { bucket, key }),
+					},
+				),
 
-			Ok(Some(DoneJobState::Failed { job_id, error })) => {
-				info!(message = "Job failed", ?job_id, ?error);
-
-				match jobqueue_client
-					.fail_job_run(&job_id, &format!("{}", error))
-					.await
-				{
-					Ok(()) => {}
-
-					Err(FailJobError::DbError(error)) => {
-						error!(
-							message = "DB error while marking job `Failed`",
-							?job_id,
-							?error
-						);
-					}
-
-					Err(FailJobError::NotRunning) => {
-						error!(
-							message = "Tried to mark a job that isn't running as `Failed`",
-							?job_id
-						);
-					}
-				}
-			}
+				// This should never fail, we handle all special cases above
+				_ => input.insert(name, PipeData::try_from(value).unwrap()),
+			};
+		}
 
-			Err(error) => {
-				error!(message = "Join error!", ?error);
-				panic!("Join error! {error:?}");
-			}
+		// Set up context
+		let mut conn = itemdb_client.new_connection().await.unwrap();
+		let trans = conn.begin().await.unwrap();
+		let context = CopperContext {
+			stream_fragment_size: config.piper_stream_fragment_size,
+			stream_channel_size: config.piper_stream_channel_size,
+			job_id: job.job_id.as_str().into(),
+			run_by_user: job.owned_by,
+			itemdb_client: itemdb_client.clone(),
+			objectstore_blob_bucket: config.piper_objectstore_storage_bucket.as_str().into(),
+			objectstore_client: client.clone(),
+			item_db_transaction: Mutex::new(trans),
+		};
+
+		// Run job
+		let res = runner
+			.run_job(context, job.pipeline, &job.job_id, input)
+			.await;
+
+		match res {
+			Err(err) => handle_start_job_error(err, &job.job_id, &jobqueue_client).await,
+			Ok(Err(error)) => handle_run_job_error(error, &job.job_id, &jobqueue_client).await,
+			Ok(Ok(())) => handle_run_job_success(&job.job_id, &jobqueue_client).await,
 		}
+	}
+}
 
-		if runner.n_running_jobs() < config.piper_max_running_jobs {
-			// Run the oldest job off the queue
-			let next = match jobqueue_client.get_queued_job().await {
-				Ok(x) => x,
-				Err(GetQueuedJobError::DbError(error)) => {
-					error!(message = "DB error while getting job", ?error);
-					tokio::time::sleep(std::time::Duration::from_secs(5)).await;
-					continue;
+async fn handle_start_job_error(
+	err: StartJobError,
+	job_id: &QueuedJobId,
+	jobqueue_client: &PgJobQueueClient,
+) {
+	match err {
+		StartJobError::BuildError(err) => {
+			match jobqueue_client
+				.builderror_job(job_id, &format!("{:?}", err))
+				.await
+			{
+				Ok(()) => {}
+
+				Err(BuildErrorJobError::DbError(error)) => {
+					error!(
+						message = "DB error while marking job `BuildError`",
+						?job_id,
+						?error
+					);
 				}
-			};
 
-			if let Some(job) = next {
-				let mut input = BTreeMap::new();
-				for (name, value) in job.input {
-					match value {
-						AttrData::Blob { bucket, key } => input.insert(
-							name,
-							PipeData::Blob {
-								source: BytesSource::S3 { bucket, key },
-							},
-						),
-
-						// This should never fail, we handle all special cases above
-						_ => input.insert(name, PipeData::try_from(value).unwrap()),
-					};
+				Err(BuildErrorJobError::NotRunning) => {
+					error!(
+						message = "Tried to mark a job that isn't running as `BuildError`",
+						?job_id
+					);
 				}
+			}
+		}
+	}
+}
 
-				let res = runner.start_job(
-					CopperContext {
-						blob_fragment_size: config.piper_blob_fragment_size,
-						stream_channel_capacity: config.piper_stream_channel_size,
-						job_id: job.job_id.as_str().into(),
-						run_by_user: job.owned_by,
-						itemdb_client: itemdb_client.clone(),
-						objectstore_blob_bucket: config
-							.piper_objectstore_storage_bucket
-							.as_str()
-							.into(),
-						objectstore_client: client.clone(),
-						transaction: Mutex::new(Transaction::new()),
-					},
-					job.pipeline,
-					&job.job_id,
-					input,
-				);
+async fn handle_run_job_error(
+	error: RunNodeError,
+	job_id: &QueuedJobId,
+	jobqueue_client: &PgJobQueueClient,
+) {
+	info!(message = "Job failed", ?job_id, ?error);
 
-				match res {
-					Ok(()) => {}
-					Err(StartJobError::BuildError(err)) => {
-						match jobqueue_client
-							.builderror_job(&job.job_id, &format!("{:?}", err))
-							.await
-						{
-							Ok(()) => {}
-
-							Err(BuildErrorJobError::DbError(error)) => {
-								error!(
-									message = "DB error while marking job `BuildError`",
-									job_id = ?job.job_id,
-									?error
-								);
-							}
-
-							Err(BuildErrorJobError::NotRunning) => {
-								error!(
-									message = "Tried to mark a job that isn't running as `BuildError`",
-									job_id = ?job.job_id
-								);
-							}
-						}
-					}
-				}
-			}
+	match jobqueue_client
+		.fail_job_run(job_id, &format!("{}", error))
+		.await
+	{
+		Ok(()) => {}
+
+		Err(FailJobError::DbError(error)) => {
+			error!(
+				message = "DB error while marking job `Failed`",
+				?job_id,
+				?error
+			);
 		}
 
-		// Sleep a little bit so we don't waste cpu cycles.
-		tokio::time::sleep(std::time::Duration::from_millis(ASYNC_POLL_AWAIT_MS)).await;
+		Err(FailJobError::NotRunning) => {
+			error!(
+				message = "Tried to mark a job that isn't running as `Failed`",
+				?job_id
+			);
+		}
+	}
+}
+
+async fn handle_run_job_success(job_id: &QueuedJobId, jobqueue_client: &PgJobQueueClient) {
+	info!(message = "Job finished successfully", ?job_id);
+
+	match jobqueue_client.success_job(job_id).await {
+		Ok(()) => {}
+
+		Err(SuccessJobError::DbError(error)) => {
+			error!(
+				message = "DB error while marking job `Failed`",
+				?job_id,
+				?error
+			);
+		}
+
+		Err(SuccessJobError::NotRunning) => {
+			error!(
+				message = "Tried to mark a job that isn't running as `Failed`",
+				?job_id
+			);
+		}
 	}
 }
diff --git a/copperd/bin/piper/src/pipeline/job.rs b/copperd/bin/piper/src/pipeline/job.rs
index ab9cdd64..b18905d5 100644
--- a/copperd/bin/piper/src/pipeline/job.rs
+++ b/copperd/bin/piper/src/pipeline/job.rs
@@ -1,24 +1,19 @@
 use copper_piper::{
 	base::{
-		Node, NodeDispatcher, NodeId, NodeOutput, NodeParameterValue, PipelineData,
-		PipelineJobContext, PipelineJobResult, PortName, RunNodeError, ThisNodeInfo,
+		Node, NodeDispatcher, NodeId, NodeParameterValue, PortName, RunNodeError, ThisNodeInfo,
 		INPUT_NODE_TYPE,
 	},
+	data::PipeData,
 	json::PipelineJson,
+	CopperContext,
 };
 use copper_util::graph::{finalized::FinalizedGraph, graph::Graph, util::GraphNodeIdx};
 use smartstring::{LazyCompact, SmartString};
 use std::{
 	collections::{BTreeMap, HashMap},
 	fmt::Debug,
-	marker::PhantomData,
-	sync::Arc,
 };
 use thiserror::Error;
-use tokio::{
-	sync::mpsc::{self, error::TryRecvError},
-	task::{JoinError, JoinSet},
-};
 use tracing::{debug, trace};
 
 use crate::config::ASYNC_POLL_AWAIT_MS;
@@ -61,32 +56,15 @@ pub enum PipelineBuildError {
 // MARK: Helper structs
 //
 
-struct NodeResult<DataType: PipelineData> {
-	result: Result<(), RunNodeError<DataType>>,
-	node_id: NodeId,
-	node_idx: GraphNodeIdx,
-}
-
-enum NodeState<
-	ResultType: PipelineJobResult,
-	DataType: PipelineData,
-	ContextType: PipelineJobContext<DataType, ResultType>,
-> {
+enum NodeState<'ctx> {
 	// Store this node's instance here, so we can take ownership
 	// of it when we run.
-	NotStarted {
-		instance: Box<dyn Node<ResultType, DataType, ContextType>>,
-	},
+	NotStarted { instance: Box<dyn Node<'ctx>> },
 	Running,
 	Done,
 }
 
-impl<
-		ResultType: PipelineJobResult,
-		DataType: PipelineData,
-		ContextType: PipelineJobContext<DataType, ResultType>,
-	> Debug for NodeState<ResultType, DataType, ContextType>
-{
+impl Debug for NodeState<'_> {
 	fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
 		match self {
 			Self::NotStarted { .. } => write!(f, "NotStarted"),
@@ -96,12 +74,7 @@ impl<
 	}
 }
 
-impl<
-		ResultType: PipelineJobResult,
-		DataType: PipelineData,
-		ContextType: PipelineJobContext<DataType, ResultType>,
-	> NodeState<ResultType, DataType, ContextType>
-{
+impl<'ctx> NodeState<'ctx> {
 	fn has_been_started(&self) -> bool {
 		return matches!(self, Self::Running | Self::Done);
 	}
@@ -116,7 +89,7 @@ impl<
 
 	/// Turn `Self::NotStarted` into `Self::Running` and return `instance`.
 	/// Returns `None` otherwise.
-	fn start(&mut self) -> Option<Box<dyn Node<ResultType, DataType, ContextType>>> {
+	fn start(&mut self) -> Option<Box<dyn Node<'ctx>>> {
 		match self {
 			Self::NotStarted { .. } => {
 				let x = std::mem::replace(self, Self::Running);
@@ -130,11 +103,7 @@ impl<
 	}
 }
 
-struct NodeSpec<
-	ResultType: PipelineJobResult,
-	DataType: PipelineData,
-	ContextType: PipelineJobContext<DataType, ResultType>,
-> {
+struct NodeSpec<'ctx> {
 	/// The node's id
 	pub id: NodeId,
 
@@ -145,17 +114,12 @@ struct NodeSpec<
 	pub node_params: BTreeMap<SmartString<LazyCompact>, NodeParameterValue>,
 
 	/// This node's state
-	pub state: NodeState<ResultType, DataType, ContextType>,
+	pub state: NodeState<'ctx>,
 }
 
 // We need to do this ourselves, since the ContextType generic
 // confuses #[derive(Debug)].
-impl<
-		ResultType: PipelineJobResult,
-		DataType: PipelineData,
-		ContextType: PipelineJobContext<DataType, ResultType>,
-	> Debug for NodeSpec<ResultType, DataType, ContextType>
-{
+impl Debug for NodeSpec<'_> {
 	fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
 		f.debug_struct("NodeSpec")
 			.field("id", &self.id)
@@ -167,16 +131,16 @@ impl<
 }
 
 #[derive(Debug)]
-enum EdgeDataContainer<DataType: PipelineData> {
+enum EdgeDataContainer {
 	Unset,
-	Some(Option<DataType>),
+	Some(Option<PipeData>),
 	Consumed,
 }
 
-impl<DataType: PipelineData> EdgeDataContainer<DataType> {
+impl EdgeDataContainer {
 	/// Takes the value out of this container, leaving [`EdgeDataContainer::Consumed`] in its place.
 	/// Does nothing and returns None if this isn't [`EdgeDataContainer::Some`].
-	pub fn take(&mut self) -> Option<Option<DataType>> {
+	pub fn take(&mut self) -> Option<Option<PipeData>> {
 		match self {
 			Self::Some(_) => {
 				let x = std::mem::replace(self, Self::Consumed);
@@ -192,10 +156,10 @@ impl<DataType: PipelineData> EdgeDataContainer<DataType> {
 }
 
 #[derive(Debug)]
-struct EdgeSpec<DataType: PipelineData> {
+struct EdgeSpec {
 	source_port: PortName,
 	target_port: PortName,
-	data: EdgeDataContainer<DataType>,
+	data: EdgeDataContainer,
 }
 
 //
@@ -208,33 +172,20 @@ struct EdgeSpec<DataType: PipelineData> {
 /// Any [`PipelineJson`] that builds into a PipelineSpec successfully
 /// should be runnable (but may encounter run-time errors)
 #[derive(Debug)]
-pub struct PipelineJob<
-	ResultType: PipelineJobResult,
-	DataType: PipelineData,
-	ContextType: PipelineJobContext<DataType, ResultType>,
-> {
-	_pa: PhantomData<DataType>,
-	_pb: PhantomData<ContextType>,
+pub struct PipelineJob<'ctx> {
 	pub job_id: SmartString<LazyCompact>,
 
-	graph: FinalizedGraph<NodeSpec<ResultType, DataType, ContextType>, EdgeSpec<DataType>>,
+	graph: FinalizedGraph<NodeSpec<'ctx>, EdgeSpec>,
 }
 
-impl<
-		ResultType: PipelineJobResult,
-		DataType: PipelineData,
-		ContextType: PipelineJobContext<DataType, ResultType>,
-	> PipelineJob<ResultType, DataType, ContextType>
-{
+impl<'ctx> PipelineJob<'ctx> {
 	pub fn new(
-		dispatcher: &NodeDispatcher<ResultType, DataType, ContextType>,
+		dispatcher: &NodeDispatcher,
 		job_id: &str,
-		input: BTreeMap<SmartString<LazyCompact>, DataType>,
+		input: BTreeMap<SmartString<LazyCompact>, PipeData>,
 		json: &PipelineJson,
 	) -> Result<Self, PipelineBuildError> {
 		return Ok(Self {
-			_pa: PhantomData {},
-			_pb: PhantomData {},
 			job_id: job_id.into(),
 			graph: Self::build(dispatcher, job_id, json, input)?,
 		});
@@ -245,16 +196,12 @@ impl<
 	//
 
 	/// Build a pipeline from its deserialized form
-	#[allow(clippy::type_complexity)]
 	fn build(
-		dispatcher: &NodeDispatcher<ResultType, DataType, ContextType>,
+		dispatcher: &NodeDispatcher,
 		job_id: &str,
 		json: &PipelineJson,
-		input: BTreeMap<SmartString<LazyCompact>, DataType>,
-	) -> Result<
-		FinalizedGraph<NodeSpec<ResultType, DataType, ContextType>, EdgeSpec<DataType>>,
-		PipelineBuildError,
-	> {
+		input: BTreeMap<SmartString<LazyCompact>, PipeData>,
+	) -> Result<FinalizedGraph<NodeSpec<'ctx>, EdgeSpec>, PipelineBuildError> {
 		trace!(message = "Building pipeline graph", job_id);
 
 		// The graph that stores this pipeline
@@ -392,9 +339,7 @@ impl<
 	// MARK: Run
 	//
 
-	pub async fn run(mut self, context: ContextType) -> Result<ResultType, RunNodeError<DataType>> {
-		let context = Arc::new(context);
-
+	pub async fn run(mut self, context: &CopperContext<'ctx>) -> Result<(), RunNodeError> {
 		trace!(
 			message = "Running job",
 			job_id = ?self.job_id,
@@ -404,18 +349,10 @@ impl<
 		let all_nodes: Vec<GraphNodeIdx> =
 			self.graph.iter_nodes_idx().map(|(idx, _)| idx).collect();
 
-		let mut tasks = JoinSet::new();
-		// TODO: configure channel size
-		let (tx, mut rx) = mpsc::channel::<NodeOutput<DataType>>(30);
-
-		// The below loop hits no awaits until something interesting happens
-		// (node finished, input received, etc)
-		//
-		// This is a problem, because this loop will block the async runtime,
-		// which prevents interesting things from happening.
-		//
-		// We've thus added `yield_now` to this loop.
-		loop {
+		while all_nodes
+			.iter()
+			.any(|x| !self.graph.get_node(*x).unwrap().state.is_done())
+		{
 			//
 			// Start nodes
 			//
@@ -433,6 +370,10 @@ impl<
 					continue;
 				}
 
+				// Only run nodes that can be run.
+				// A node can be run if...
+				// - it hasn't already been run
+				// - all its inputs are ready
 				let can_be_run =
 					self.graph
 						.edges_ending_at(node_idx)
@@ -452,7 +393,7 @@ impl<
 				}
 
 				// Take all inputs
-				let node_run_input: BTreeMap<PortName, Option<DataType>> = {
+				let node_run_input: BTreeMap<PortName, Option<PipeData>> = {
 					let input_edges = Vec::from(self.graph.edges_ending_at(node_idx).unwrap());
 					input_edges
 						.into_iter()
@@ -463,180 +404,105 @@ impl<
 						.collect()
 				};
 
-				// Borrow again as mutable
 				let node = self.graph.get_node_mut(node_idx).unwrap();
-				let ctx = context.clone();
-				let params = node.node_params.clone();
-				let node_id = node.id.clone();
-				let node_type = node.node_type.clone();
-				let tx = tx.clone();
 				let node_inst = node.state.start().unwrap();
-				let job_id = self.job_id.clone();
 
 				debug!(
 					message = "Starting node",
-					node_type = ?node_type,
-					node_id = ?node_id,
-					job_id = ?job_id,
-					tasks = tasks.len(),
+					node_type = ?node.node_type,
+					node_id = ?node.id,
+					job_id = ?self.job_id,
 				);
 
-				tasks.spawn(async move {
-					// This log helps detect a blocked async runtime
-					// (i.e, tokio is stuck if you see "Starting node" and not "Started node")
-					trace!(
-						message = "Started node",
-						node_type = ?node_type,
-						node_id = ?node_id,
-						job_id = ?job_id,
-					);
-
-					let result = node_inst
-						.run(
-							&ctx,
-							ThisNodeInfo {
-								id: node_id.clone(),
-								idx: node_idx,
-								node_type: node_type.clone(),
-							},
-							params,
-							node_run_input,
-							tx,
-						)
-						.await;
-
-					NodeResult {
-						result,
-						node_id,
-						node_idx,
+				//
+				// MARK: Run node
+				//
+
+				let result = match node_inst
+					.run(
+						context,
+						ThisNodeInfo {
+							id: node.id.clone(),
+							idx: node_idx,
+							node_type: node.node_type.clone(),
+						},
+						node.node_params.clone().into(),
+						node_run_input,
+					)
+					.await
+				{
+					Ok(x) => x,
+					Err(error) => {
+						debug!(
+							message = "Node finished with error",
+							node_id = ?node.id,
+							job_id = ?self.job_id,
+							?error
+						);
+						return Err(error);
 					}
-				});
-			}
+				};
 
-			tokio::task::yield_now().await;
+				trace!(
+					message = "Node done, processing output",
+					node_type = ?node.node_type,
+					node_id = ?node.id,
+					job_id = ?self.job_id,
+				);
 
-			//
-			// Process node output
-			//
-			loop {
-				match rx.try_recv() {
-					Err(TryRecvError::Empty) => {
-						break;
+				//
+				// MARK: Process output
+				//
+
+				// Send output to edges
+				let node_id = node.id.clone();
+				let node_type = node.node_type.clone();
+
+				for (from_node, _to_node, edge) in self.graph.iter_edges_mut() {
+					if from_node != node_idx {
+						continue;
 					}
 
-					Err(TryRecvError::Disconnected) => {
-						panic!()
+					if !matches!(edge.data, EdgeDataContainer::Unset) {
+						return Err(RunNodeError::OutputPortSetTwice {
+							node_id,
+							node_type,
+							port: edge.source_port.clone(),
+						});
 					}
 
-					Ok(x) => self.process_node_output(x)?,
+					edge.data = EdgeDataContainer::Some(result.get(&edge.source_port).cloned());
 				}
-			}
-
-			tokio::task::yield_now().await;
-
-			//
-			// Process finished tasks
-			//
-			while let Some(res) = tasks.try_join_next() {
-				self.process_finished_node(res)?
-			}
 
-			//
-			// Exit if we have no more tasks to run
-			// (i.e, if there are no pending tasks AND all nodes are done)
-			//
-			if tasks.is_empty()
-				&& all_nodes
-					.iter()
-					.all(|x| self.graph.get_node(*x).unwrap().state.is_done())
-			{
-				break;
-			}
+				//
+				// MARK: finish node
+				//
 
-			tokio::time::sleep(std::time::Duration::from_millis(ASYNC_POLL_AWAIT_MS)).await;
-		}
-
-		return match Arc::into_inner(context) {
-			Some(x) => Ok(x.to_result()?),
-			None => unreachable!(),
-		};
-	}
-
-	//
-	// MARK: Process task results
-	//
-	fn process_node_output(
-		&mut self,
-		out: NodeOutput<DataType>,
-	) -> Result<(), RunNodeError<DataType>> {
-		trace!(
-			message = "Processing node output",
-			node_type= ?out.node.node_type,
-			node_id = ?out.node.id,
-			job_id = ?self.job_id,
-		);
-
-		// Send output to edges
-		for (from_node, _to_node, edge) in self.graph.iter_edges_mut() {
-			if from_node != out.node.idx || edge.source_port != out.port {
-				continue;
-			}
-
-			if !matches!(edge.data, EdgeDataContainer::Unset) {
-				return Err(RunNodeError::OutputPortSetTwice {
-					node_id: out.node.id,
-					node_type: out.node.node_type,
-					port: edge.source_port.clone(),
-				});
-			}
-
-			edge.data = EdgeDataContainer::Some(out.data.clone());
-		}
-
-		return Ok(());
-	}
-
-	fn process_finished_node(
-		&mut self,
-		res: Result<NodeResult<DataType>, JoinError>,
-	) -> Result<(), RunNodeError<DataType>> {
-		let res = res?;
-		let node = self.graph.get_node_mut(res.node_idx).unwrap();
+				// re-borrow again, we needed a &mut graph above
+				let node = self.graph.get_node_mut(node_idx).unwrap();
 
-		assert!(
-			node.state.is_running(),
-			"Expected node to be running. node: {node:?}"
-		);
+				assert!(
+					node.state.is_running(),
+					"Expected node to be running. node: {node:?}"
+				);
 
-		node.state = NodeState::Done;
+				node.state = NodeState::Done;
 
-		if let Err(err) = res.result {
-			debug!(
-				message = "Node run failed",
-				node_id = ?res.node_id,
-				job_id = ?self.job_id,
-				error = format!("{err:?}")
-			);
-			return Err(err);
-		} else {
-			debug!(
-				message = "Node finished without error",
-				node_id = ?res.node_id,
-				job_id = ?self.job_id,
-			);
-		}
+				// Make sure all edges starting at this node got output
+				for (from_node, _to_node, edge) in self.graph.iter_edges_mut() {
+					if from_node != node_idx {
+						continue;
+					}
 
-		// Make sure all edges starting at this node got output
-		for (from_node, _to_node, edge) in self.graph.iter_edges_mut() {
-			if from_node != res.node_idx {
-				continue;
+					if matches!(edge.data, EdgeDataContainer::Unset) {
+						return Err(RunNodeError::UnrecognizedOutput {
+							port: edge.source_port.clone(),
+						});
+					}
+				}
 			}
 
-			if matches!(edge.data, EdgeDataContainer::Unset) {
-				return Err(RunNodeError::UnrecognizedOutput {
-					port: edge.source_port.clone(),
-				});
-			}
+			tokio::time::sleep(std::time::Duration::from_millis(ASYNC_POLL_AWAIT_MS)).await;
 		}
 
 		return Ok(());
diff --git a/copperd/bin/piper/src/pipeline/runner.rs b/copperd/bin/piper/src/pipeline/runner.rs
index 612338dc..9e239adc 100644
--- a/copperd/bin/piper/src/pipeline/runner.rs
+++ b/copperd/bin/piper/src/pipeline/runner.rs
@@ -1,12 +1,13 @@
 use copper_jobqueue::id::QueuedJobId;
 use copper_piper::{
-	base::{NodeDispatcher, PipelineData, PipelineJobContext, PipelineJobResult, RunNodeError},
+	base::{NodeDispatcher, RunNodeError},
+	data::PipeData,
 	json::PipelineJson,
+	CopperContext,
 };
 use smartstring::{LazyCompact, SmartString};
-use std::collections::BTreeMap;
+use std::{collections::BTreeMap, sync::Arc};
 use thiserror::Error;
-use tokio::task::{JoinError, JoinSet};
 use tracing::debug;
 
 use super::job::PipelineBuildError;
@@ -22,120 +23,51 @@ pub enum StartJobError {
 	BuildError(#[from] PipelineBuildError),
 }
 
-//
-// MARK: helpers
-//
-
-pub enum DoneJobState<ResultType: PipelineJobResult, DataType: PipelineData> {
-	Failed {
-		job_id: QueuedJobId,
-		error: RunNodeError<DataType>,
-	},
-	Success {
-		job_id: QueuedJobId,
-		result: ResultType,
-	},
-}
-
 //
 // MARK: Runner
 //
 
-pub struct PipelineRunner<
-	ResultType: PipelineJobResult,
-	DataType: PipelineData,
-	ContextType: PipelineJobContext<DataType, ResultType>,
-> {
-	dispatcher: NodeDispatcher<ResultType, DataType, ContextType>,
-
-	/// Jobs that are running right now
-	#[allow(clippy::type_complexity)]
-	tasks: JoinSet<(QueuedJobId, Result<ResultType, RunNodeError<DataType>>)>,
+pub struct PipelineRunner {
+	dispatcher: NodeDispatcher,
 }
 
-impl<
-		ResultType: PipelineJobResult,
-		DataType: PipelineData,
-		ContextType: PipelineJobContext<DataType, ResultType>,
-	> PipelineRunner<ResultType, DataType, ContextType>
-{
+impl PipelineRunner {
 	/// Initialize a new runner
 	pub fn new() -> Self {
 		Self {
 			dispatcher: NodeDispatcher::new(),
-			tasks: JoinSet::new(),
 		}
 	}
 
 	/// Start a job in this runner
-	pub fn start_job(
+	pub async fn run_job(
 		&mut self,
-		context: ContextType,
+		context: CopperContext<'_>,
 		pipeline: PipelineJson,
 		job_id: &QueuedJobId,
-		inputs: BTreeMap<SmartString<LazyCompact>, DataType>,
-	) -> Result<(), StartJobError> {
-		debug!(
-			message = "Starting job",
-			?job_id,
-			running_jobs = self.tasks.len(),
-		);
-
-		let job = PipelineJob::<ResultType, DataType, ContextType>::new(
-			&self.dispatcher,
-			job_id.as_str(),
-			inputs.clone(),
-			&pipeline,
-		)?;
-
-		let job_id_cloned = job_id.clone();
-		self.tasks.spawn(async {
-			// TODO: handle error
-			let x = job.run(context).await;
-			(job_id_cloned, x)
-		});
-
-		return Ok(());
-	}
-
-	/// If any job is done, return its state.
-	/// otherwise, return [`None`].
-	pub async fn check_done_jobs(
-		&mut self,
-	) -> Result<Option<DoneJobState<ResultType, DataType>>, JoinError> {
-		if let Some(res) = self.tasks.try_join_next() {
-			let res = res?;
-
-			if let Err(error) = res.1 {
-				return Ok(Some(DoneJobState::Failed {
-					job_id: res.0.clone(),
-					error,
-				}));
-			} else {
-				return Ok(Some(DoneJobState::Success {
-					job_id: res.0.clone(),
-					result: res.1.unwrap(),
-				}));
+		inputs: BTreeMap<SmartString<LazyCompact>, PipeData>,
+	) -> Result<Result<(), RunNodeError>, StartJobError> {
+		debug!(message = "Starting job", ?job_id,);
+
+		let job = PipelineJob::new(&self.dispatcher, job_id.as_str(), inputs.clone(), &pipeline)?;
+		let x = job.run(&context).await;
+
+		if x.is_ok() {
+			// Commit only if job ran successfully
+			let trans = context.item_db_transaction.into_inner();
+			match trans.commit().await {
+				Ok(()) => {}
+				Err(e) => return Ok(Err(Arc::new(e).into())),
 			}
 		}
 
-		return Ok(None);
+		return Ok(x);
 	}
 }
 
-impl<
-		ResultType: PipelineJobResult,
-		DataType: PipelineData,
-		ContextType: PipelineJobContext<DataType, ResultType>,
-	> PipelineRunner<ResultType, DataType, ContextType>
-{
+impl PipelineRunner {
 	/// Get this runner's node dispatcher
-	pub fn mut_dispatcher(&mut self) -> &mut NodeDispatcher<ResultType, DataType, ContextType> {
+	pub fn mut_dispatcher(&mut self) -> &mut NodeDispatcher {
 		&mut self.dispatcher
 	}
-
-	/// Return the number of jobs that are currently running
-	pub fn n_running_jobs(&self) -> usize {
-		self.tasks.len()
-	}
 }
diff --git a/copperd/lib/itemdb/src/client/base/client.rs b/copperd/lib/itemdb/src/client/base/client.rs
deleted file mode 100644
index 41513b1d..00000000
--- a/copperd/lib/itemdb/src/client/base/client.rs
+++ /dev/null
@@ -1,118 +0,0 @@
-//! The database client api
-
-use crate::{
-	transaction::Transaction, AttrDataStub, AttributeId, AttributeInfo, AttributeOptions, ClassId,
-	ClassInfo, DatasetId, DatasetInfo, ItemId, ItemInfo, UserId,
-};
-use async_trait::async_trait;
-
-use super::errors::{
-	attribute::{AddAttributeError, DeleteAttributeError, GetAttributeError, RenameAttributeError},
-	class::{AddClassError, DeleteClassError, GetClassError, RenameClassError},
-	dataset::{
-		AddDatasetError, DeleteDatasetError, GetDatasetError, ListDatasetsError, RenameDatasetError,
-	},
-	item::{CountItemsError, GetItemError, ListItemsError},
-	transaction::ApplyTransactionError,
-};
-
-/// A generic database client
-#[async_trait]
-pub trait ItemdbClient
-where
-	Self: Send + Sync,
-{
-	//
-	// MARK: Dataset
-	//
-
-	/// Create a new dataset
-	async fn add_dataset(&self, name: &str, owner: UserId) -> Result<DatasetId, AddDatasetError>;
-
-	/// Get dataset details
-	async fn get_dataset(&self, dataset: DatasetId) -> Result<DatasetInfo, GetDatasetError>;
-
-	/// Get all a user's datasets
-	async fn list_datasets(&self, owner: UserId) -> Result<Vec<DatasetInfo>, ListDatasetsError>;
-
-	/// Rename a dataset
-	async fn rename_dataset(
-		&self,
-		dataset: DatasetId,
-		new_name: &str,
-	) -> Result<(), RenameDatasetError>;
-
-	/// Delete a dataset
-	async fn del_dataset(&self, dataset: DatasetId) -> Result<(), DeleteDatasetError>;
-
-	//
-	// MARK: Class
-	//
-
-	/// Create a new class in a dataset
-	async fn add_class(&self, in_dataset: DatasetId, name: &str) -> Result<ClassId, AddClassError>;
-
-	/// Get class details
-	async fn get_class(&self, class: ClassId) -> Result<ClassInfo, GetClassError>;
-
-	/// Rename a class
-	async fn rename_class(&self, class: ClassId, new_name: &str) -> Result<(), RenameClassError>;
-
-	/// Delete a class
-	async fn del_class(&self, class: ClassId) -> Result<(), DeleteClassError>;
-
-	//
-	// MARK: Attribute
-	//
-
-	/// Create a new attribute in a class
-	async fn add_attribute(
-		&self,
-		in_class: ClassId,
-		name: &str,
-		with_type: AttrDataStub,
-		options: AttributeOptions,
-	) -> Result<AttributeId, AddAttributeError>;
-
-	/// Get attribute details
-	async fn get_attribute(
-		&self,
-		attribute: AttributeId,
-	) -> Result<AttributeInfo, GetAttributeError>;
-
-	/// Rename an attribute
-	async fn rename_attribute(
-		&self,
-		attribute: AttributeId,
-		new_name: &str,
-	) -> Result<(), RenameAttributeError>;
-
-	/// Delete an attribute
-	async fn del_attribute(&self, attribute: AttributeId) -> Result<(), DeleteAttributeError>;
-
-	//
-	// MARK: Item
-	//
-
-	/// Get item details
-	async fn get_item(&self, item: ItemId) -> Result<ItemInfo, GetItemError>;
-
-	async fn list_items(
-		&self,
-		class: ClassId,
-		skip: i64,
-		count: usize,
-	) -> Result<Vec<ItemInfo>, ListItemsError>;
-
-	async fn count_items(&self, class: ClassId) -> Result<i64, CountItemsError>;
-
-	//
-	// MARK: Transactions
-	//
-
-	/// Apply the given transaction the database
-	async fn apply_transaction(
-		&self,
-		transaction: Transaction,
-	) -> Result<(), ApplyTransactionError>;
-}
diff --git a/copperd/lib/itemdb/src/client/base/errors/transaction.rs b/copperd/lib/itemdb/src/client/base/errors/transaction.rs
deleted file mode 100644
index 261124ae..00000000
--- a/copperd/lib/itemdb/src/client/base/errors/transaction.rs
+++ /dev/null
@@ -1,31 +0,0 @@
-//! Errors we can encounter when operating on attributes
-use thiserror::Error;
-
-use crate::transaction::AddItemError;
-
-/// An error we can encounter when creating an attribute
-#[derive(Debug, Error)]
-pub enum ApplyTransactionError {
-	/// Database error
-	#[error("database backend error")]
-	DbError(#[from] sqlx::Error),
-
-	/// We encountered an error while adding an item
-	#[error("error while creating item")]
-	AddItemError(#[from] AddItemError),
-
-	/// A transaction action referenced the result of another transaction,
-	/// but that other transaction doesn't exist or hasn't been computed yet.
-	#[error("referenced an action that doesn't exist")]
-	ReferencedBadAction,
-
-	/// A transaction action referenced the result of another transaction,
-	/// but that other transaction produced a `None` result
-	#[error("referenced result with `None` return type")]
-	ReferencedNoneResult,
-
-	/// A transaction action referenced the result of another transaction,
-	/// but that other transaction produced a result with an unexpected type.
-	#[error("referenced result with unexpected type")]
-	ReferencedResultWithBadType,
-}
diff --git a/copperd/lib/itemdb/src/client/base/mod.rs b/copperd/lib/itemdb/src/client/base/mod.rs
deleted file mode 100644
index 15e3cbdb..00000000
--- a/copperd/lib/itemdb/src/client/base/mod.rs
+++ /dev/null
@@ -1,4 +0,0 @@
-//! This crate defines a backend-agnostic database client api
-
-pub mod client;
-pub mod errors;
diff --git a/copperd/lib/itemdb/src/client/client/attribute.rs b/copperd/lib/itemdb/src/client/client/attribute.rs
new file mode 100644
index 00000000..908fc91e
--- /dev/null
+++ b/copperd/lib/itemdb/src/client/client/attribute.rs
@@ -0,0 +1,148 @@
+//! This modules contains Copper's itemdb client
+
+use copper_util::names::check_name;
+use sqlx::Row;
+
+use crate::{
+	client::errors::attribute::{
+		AddAttributeError, DeleteAttributeError, GetAttributeError, RenameAttributeError,
+	},
+	AttrDataStub, AttributeId, AttributeInfo, AttributeOptions, ClassId,
+};
+
+use super::ItemdbClient;
+
+impl ItemdbClient {
+	pub async fn add_attribute(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		in_class: ClassId,
+		name: &str,
+		with_type: AttrDataStub,
+		options: AttributeOptions,
+	) -> Result<AttributeId, AddAttributeError> {
+		match check_name(name) {
+			Ok(()) => {}
+			Err(e) => return Err(AddAttributeError::NameError(e)),
+		}
+
+		// If we're trying to create a notnull attribute,
+		// we need to ensure that no new null fields are created.
+		// ...in other words, we must make sure that no items exist.
+		if options.is_not_null {
+			let res = sqlx::query("SELECT COUNT(id) FROM item WHERE class_id=$1;")
+				.bind(i64::from(in_class))
+				.fetch_one(&mut **t)
+				.await?;
+			let item_count = res.get::<i64, _>("count");
+
+			if item_count != 0 {
+				return Err(AddAttributeError::CreatedNotNullWhenItemsExist);
+			}
+		}
+
+		let res = sqlx::query(
+			"INSERT INTO attribute(class_id, attr_order, pretty_name, data_type, is_unique, is_not_null)
+			SELECT $1, COALESCE(MAX(attr_order) + 1 , 0), $2, $3, $4, $5 FROM attribute WHERE class_id=$6
+			RETURNING id;",
+		)
+		.bind(i64::from(in_class))
+		.bind(name)
+		.bind(serde_json::to_string(&with_type).unwrap())
+		.bind(options.is_unique)
+		.bind(options.is_not_null)
+		.bind(i64::from(in_class))
+		.fetch_one(&mut **t)
+		.await;
+
+		let new_handle: AttributeId = match res {
+			Ok(res) => res.get::<i64, _>("id").into(),
+			Err(sqlx::Error::Database(e)) => {
+				if e.is_foreign_key_violation() {
+					return Err(AddAttributeError::NoSuchClass);
+				} else if e.is_unique_violation() {
+					return Err(AddAttributeError::UniqueViolation);
+				} else {
+					return Err(sqlx::Error::Database(e).into());
+				}
+			}
+			Err(e) => return Err(e.into()),
+		};
+
+		return Ok(new_handle);
+	}
+
+	pub async fn get_attribute(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		attribute: AttributeId,
+	) -> Result<AttributeInfo, GetAttributeError> {
+		let res = sqlx::query("SELECT * FROM attribute WHERE id=$1;")
+			.bind(i64::from(attribute))
+			.fetch_one(&mut **t)
+			.await;
+
+		return match res {
+			Err(sqlx::Error::RowNotFound) => Err(GetAttributeError::NotFound),
+			Err(e) => Err(e.into()),
+			Ok(res) => Ok(AttributeInfo {
+				id: res.get::<i64, _>("id").into(),
+				class: res.get::<i64, _>("class_id").into(),
+				order: res.get::<i64, _>("attr_order"),
+				name: res.get::<String, _>("pretty_name").into(),
+				data_type: serde_json::from_str(res.get::<&str, _>("data_type")).unwrap(),
+				options: AttributeOptions {
+					is_unique: res.get("is_unique"),
+					is_not_null: res.get("is_not_null"),
+				},
+			}),
+		};
+	}
+
+	pub async fn rename_attribute(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		attribute: AttributeId,
+		new_name: &str,
+	) -> Result<(), RenameAttributeError> {
+		match check_name(new_name) {
+			Ok(()) => {}
+			Err(e) => return Err(RenameAttributeError::NameError(e)),
+		}
+
+		let res = sqlx::query("UPDATE attribute SET pretty_name=$1 WHERE id=$2;")
+			.bind(new_name)
+			.bind(i64::from(attribute))
+			.execute(&mut **t)
+			.await;
+
+		return match res {
+			Ok(_) => Ok(()),
+
+			Err(sqlx::Error::Database(e)) => {
+				if e.is_unique_violation() {
+					Err(RenameAttributeError::UniqueViolation)
+				} else {
+					Err(sqlx::Error::Database(e).into())
+				}
+			}
+
+			Err(e) => Err(e.into()),
+		};
+	}
+
+	pub async fn del_attribute(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		attribute: AttributeId,
+	) -> Result<(), DeleteAttributeError> {
+		// This also deletes all attribute entries, etc,
+		// since they're marked with ON DELETE CASCADE.
+		sqlx::query("DELETE FROM attribute WHERE id=$1;")
+			.bind(i64::from(attribute))
+			.execute(&mut **t)
+			.await?;
+
+		return Ok(());
+	}
+}
diff --git a/copperd/lib/itemdb/src/client/client/class.rs b/copperd/lib/itemdb/src/client/client/class.rs
new file mode 100644
index 00000000..57ba5fa7
--- /dev/null
+++ b/copperd/lib/itemdb/src/client/client/class.rs
@@ -0,0 +1,190 @@
+//! This modules contains Copper's itemdb client
+
+use copper_util::names::check_name;
+use sqlx::Row;
+
+use crate::{
+	client::errors::class::{
+		AddClassError, ClassPrimaryAttributeError, DeleteClassError, GetClassError,
+		RenameClassError,
+	},
+	AttrDataStub, AttributeInfo, AttributeOptions, ClassId, ClassInfo, DatasetId,
+};
+
+use super::ItemdbClient;
+
+impl ItemdbClient {
+	//
+	// MARK: crud
+	//
+
+	pub async fn add_class(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		in_dataset: DatasetId,
+		name: &str,
+	) -> Result<ClassId, AddClassError> {
+		match check_name(name) {
+			Ok(()) => {}
+			Err(e) => return Err(AddClassError::NameError(e)),
+		}
+
+		let res = sqlx::query(
+			"INSERT INTO class (dataset_id, pretty_name) VALUES ($1, $2) RETURNING id;",
+		)
+		.bind(i64::from(in_dataset))
+		.bind(name)
+		.fetch_one(&mut **t)
+		.await;
+
+		let new_handle: ClassId = match res {
+			Ok(res) => res.get::<i64, _>("id").into(),
+			Err(sqlx::Error::Database(e)) => {
+				if e.is_foreign_key_violation() {
+					return Err(AddClassError::NoSuchDataset);
+				} else if e.is_unique_violation() {
+					return Err(AddClassError::UniqueViolation);
+				} else {
+					return Err(sqlx::Error::Database(e).into());
+				}
+			}
+			Err(e) => return Err(e.into()),
+		};
+		return Ok(new_handle);
+	}
+
+	pub async fn get_class(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		class: ClassId,
+	) -> Result<ClassInfo, GetClassError> {
+		let rows = sqlx::query("SELECT * FROM attribute WHERE class_id=$1;")
+			.bind(i64::from(class))
+			.fetch_all(&mut **t)
+			.await?;
+
+		let attributes = rows
+			.into_iter()
+			.map(|row| AttributeInfo {
+				id: row.get::<i64, _>("id").into(),
+				class: row.get::<i64, _>("id").into(),
+				order: row.get::<i64, _>("attr_order"),
+				name: row.get::<String, _>("pretty_name").into(),
+				data_type: serde_json::from_str(row.get::<&str, _>("data_type")).unwrap(),
+				options: AttributeOptions {
+					is_unique: row.get("is_unique"),
+					is_not_null: row.get("is_not_null"),
+				},
+			})
+			.collect();
+
+		let res = sqlx::query("SELECT COUNT(id) FROM item WHERE class_id=$1;")
+			.bind(i64::from(class))
+			.fetch_one(&mut **t)
+			.await?;
+
+		let item_count = res.get::<i64, _>("count").try_into().unwrap();
+
+		let res = sqlx::query("SELECT * FROM class WHERE id=$1;")
+			.bind(i64::from(class))
+			.fetch_one(&mut **t)
+			.await;
+
+		return match res {
+			Err(sqlx::Error::RowNotFound) => Err(GetClassError::NotFound),
+			Err(e) => Err(e.into()),
+			Ok(res) => Ok(ClassInfo {
+				dataset: res.get::<i64, _>("dataset_id").into(),
+				id: res.get::<i64, _>("id").into(),
+				name: res.get::<String, _>("pretty_name").into(),
+				attributes,
+				item_count,
+			}),
+		};
+	}
+
+	pub async fn rename_class(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		class: ClassId,
+		new_name: &str,
+	) -> Result<(), RenameClassError> {
+		match check_name(new_name) {
+			Ok(()) => {}
+			Err(e) => return Err(RenameClassError::NameError(e)),
+		}
+
+		let res = sqlx::query("UPDATE class SET pretty_name=$1 WHERE id=$2;")
+			.bind(new_name)
+			.bind(i64::from(class))
+			.execute(&mut **t)
+			.await;
+
+		return match res {
+			Err(sqlx::Error::Database(e)) => {
+				if e.is_unique_violation() {
+					Err(RenameClassError::UniqueViolation)
+				} else {
+					Err(sqlx::Error::Database(e).into())
+				}
+			}
+
+			Err(e) => Err(e.into()),
+
+			Ok(_) => Ok(()),
+		};
+	}
+
+	pub async fn del_class(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		class: ClassId,
+	) -> Result<(), DeleteClassError> {
+		// This also deletes all classes, attributes, etc,
+		// since they're marked with ON DELETE CASCADE.
+		sqlx::query("DELETE FROM class WHERE id=$1;")
+			.bind(i64::from(class))
+			.execute(&mut **t)
+			.await?;
+
+		return Ok(());
+	}
+
+	//
+	// MARK: misc
+	//
+
+	/// Get the attribute we should use to represent this class.
+	/// This is used as an item preview in the `Reference` ui panel.
+	///
+	/// If this returns `None`, the class has no valid attributes
+	pub async fn class_primary_attr(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		class: ClassId,
+	) -> Result<Option<AttributeInfo>, ClassPrimaryAttributeError> {
+		let class = self.get_class(t, class).await.map_err(|e| match e {
+			GetClassError::NotFound => ClassPrimaryAttributeError::NotFound,
+			GetClassError::DbError(err) => ClassPrimaryAttributeError::DbError(err),
+		})?;
+
+		// If we have blobs, return the first one
+		for attr in &class.attributes {
+			match attr.data_type {
+				AttrDataStub::Blob => return Ok(Some(attr.clone())),
+				_ => continue,
+			}
+		}
+
+		// Otherwise, return the first non-reference attribute
+		// This prevents infinite loops that might occur we have a ref cycle.
+		for attr in &class.attributes {
+			match attr.data_type {
+				AttrDataStub::Reference { .. } => continue,
+				_ => return Ok(Some(attr.clone())),
+			}
+		}
+
+		return Ok(None);
+	}
+}
diff --git a/copperd/lib/itemdb/src/client/client/dataset.rs b/copperd/lib/itemdb/src/client/client/dataset.rs
new file mode 100644
index 00000000..663f154b
--- /dev/null
+++ b/copperd/lib/itemdb/src/client/client/dataset.rs
@@ -0,0 +1,239 @@
+use copper_util::names::check_name;
+use sqlx::Row;
+
+use crate::{
+	client::errors::dataset::{
+		AddDatasetError, DeleteDatasetError, GetDatasetError, ListDatasetsError, RenameDatasetError,
+	},
+	AttributeInfo, AttributeOptions, ClassId, ClassInfo, DatasetId, DatasetInfo, UserId,
+};
+
+use super::ItemdbClient;
+
+impl ItemdbClient {
+	pub async fn add_dataset(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		name: &str,
+		user: UserId,
+	) -> Result<DatasetId, AddDatasetError> {
+		match check_name(name) {
+			Ok(()) => {}
+			Err(e) => return Err(AddDatasetError::NameError(e)),
+		}
+
+		let res =
+			sqlx::query("INSERT INTO dataset (pretty_name, owner) VALUES ($1, $2) RETURNING id;")
+				.bind(name)
+				.bind(i64::from(user))
+				.fetch_one(&mut **t)
+				.await;
+
+		let new_handle: DatasetId = match res {
+			Ok(res) => res.get::<i64, _>("id").into(),
+			Err(sqlx::Error::Database(e)) => {
+				if e.is_unique_violation() {
+					return Err(AddDatasetError::UniqueViolation);
+				} else {
+					return Err(sqlx::Error::Database(e).into());
+				}
+			}
+			Err(e) => return Err(e.into()),
+		};
+
+		return Ok(new_handle);
+	}
+
+	pub async fn get_dataset(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		dataset: DatasetId,
+	) -> Result<DatasetInfo, GetDatasetError> {
+		let classes: Vec<ClassInfo> = {
+			let rows = sqlx::query("SELECT * FROM class WHERE dataset_id=$1;")
+				.bind(i64::from(dataset))
+				.fetch_all(&mut **t)
+				.await?;
+
+			let mut classes = Vec::new();
+
+			for r in rows {
+				let class_id: ClassId = r.get::<i64, _>("id").into();
+
+				let attr_rows = sqlx::query("SELECT * FROM attribute WHERE class_id=$1;")
+					.bind(i64::from(class_id))
+					.fetch_all(&mut **t)
+					.await?;
+
+				let attributes = attr_rows
+					.into_iter()
+					.map(|row| AttributeInfo {
+						id: row.get::<i64, _>("id").into(),
+						class: row.get::<i64, _>("id").into(),
+						order: row.get::<i64, _>("attr_order"),
+						name: row.get::<String, _>("pretty_name").into(),
+						data_type: serde_json::from_str(row.get::<&str, _>("data_type")).unwrap(),
+						options: AttributeOptions {
+							is_unique: row.get("is_unique"),
+							is_not_null: row.get("is_not_null"),
+						},
+					})
+					.collect();
+
+				let res = sqlx::query("SELECT COUNT(id) FROM item WHERE class_id=$1;")
+					.bind(i64::from(class_id))
+					.fetch_one(&mut **t)
+					.await?;
+
+				let item_count = res.get::<i64, _>("count").try_into().unwrap();
+
+				classes.push(ClassInfo {
+					dataset,
+					id: class_id,
+					name: r.get::<String, _>("pretty_name").into(),
+					attributes,
+					item_count,
+				});
+			}
+
+			classes
+		};
+
+		let res = sqlx::query("SELECT * FROM dataset WHERE id=$1;")
+			.bind(i64::from(dataset))
+			.fetch_one(&mut **t)
+			.await;
+
+		return match res {
+			Err(sqlx::Error::RowNotFound) => Err(GetDatasetError::NotFound),
+			Err(e) => Err(e.into()),
+			Ok(res) => Ok(DatasetInfo {
+				id: res.get::<i64, _>("id").into(),
+				owner: res.get::<i64, _>("owner").into(),
+				name: res.get::<String, _>("pretty_name").into(),
+				classes,
+			}),
+		};
+	}
+
+	pub async fn list_datasets(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		owner: UserId,
+	) -> Result<Vec<DatasetInfo>, ListDatasetsError> {
+		let rows = sqlx::query("SELECT * FROM dataset WHERE owner=$1;")
+			.bind(i64::from(owner))
+			.fetch_all(&mut **t)
+			.await?;
+
+		let mut out = Vec::new();
+		for row in rows {
+			let dataset_id = row.get::<i64, _>("id").into();
+
+			let classes: Vec<ClassInfo> = {
+				let rows = sqlx::query("SELECT * FROM class WHERE dataset_id=$1;")
+					.bind(i64::from(dataset_id))
+					.fetch_all(&mut **t)
+					.await?;
+
+				let mut classes = Vec::new();
+
+				for r in rows {
+					let class_id: ClassId = r.get::<i64, _>("id").into();
+
+					let attr_rows = sqlx::query("SELECT * FROM attribute WHERE class_id=$1;")
+						.bind(i64::from(class_id))
+						.fetch_all(&mut **t)
+						.await?;
+
+					let attributes = attr_rows
+						.into_iter()
+						.map(|row| AttributeInfo {
+							id: row.get::<i64, _>("id").into(),
+							class: row.get::<i64, _>("id").into(),
+							order: row.get::<i64, _>("attr_order"),
+							name: row.get::<String, _>("pretty_name").into(),
+							data_type: serde_json::from_str(row.get::<&str, _>("data_type"))
+								.unwrap(),
+							options: AttributeOptions {
+								is_unique: row.get("is_unique"),
+								is_not_null: row.get("is_not_null"),
+							},
+						})
+						.collect();
+
+					let res = sqlx::query("SELECT COUNT(id) FROM item WHERE class_id=$1;")
+						.bind(i64::from(class_id))
+						.fetch_one(&mut **t)
+						.await?;
+
+					let item_count = res.get::<i64, _>("count").try_into().unwrap();
+
+					classes.push(ClassInfo {
+						dataset: dataset_id,
+						id: class_id,
+						name: r.get::<String, _>("pretty_name").into(),
+						attributes,
+						item_count,
+					});
+				}
+
+				classes
+			};
+
+			out.push(DatasetInfo {
+				id: dataset_id,
+				owner: row.get::<i64, _>("owner").into(),
+				name: row.get::<String, _>("pretty_name").into(),
+				classes,
+			});
+		}
+
+		return Ok(out);
+	}
+
+	pub async fn rename_dataset(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		dataset: DatasetId,
+		new_name: &str,
+	) -> Result<(), RenameDatasetError> {
+		match check_name(new_name) {
+			Ok(()) => {}
+			Err(e) => return Err(RenameDatasetError::NameError(e)),
+		}
+
+		let res = sqlx::query("UPDATE dataset SET pretty_name=$1 WHERE id=$2;")
+			.bind(new_name)
+			.bind(i64::from(dataset))
+			.execute(&mut **t)
+			.await;
+
+		return match res {
+			Ok(_) => Ok(()),
+			Err(sqlx::Error::Database(e)) => {
+				if e.is_unique_violation() {
+					Err(RenameDatasetError::UniqueViolation)
+				} else {
+					Err(sqlx::Error::Database(e).into())
+				}
+			}
+			Err(e) => Err(e.into()),
+		};
+	}
+
+	pub async fn del_dataset(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		dataset: DatasetId,
+	) -> Result<(), DeleteDatasetError> {
+		// This also deletes all attributes, etc,
+		// since they're marked with ON DELETE CASCADE.
+		sqlx::query("DELETE FROM dataset WHERE id=$1;")
+			.bind(i64::from(dataset))
+			.execute(&mut **t)
+			.await?;
+
+		return Ok(());
+	}
+}
diff --git a/copperd/lib/itemdb/src/client/client/item.rs b/copperd/lib/itemdb/src/client/client/item.rs
new file mode 100644
index 00000000..51ca4fbf
--- /dev/null
+++ b/copperd/lib/itemdb/src/client/client/item.rs
@@ -0,0 +1,329 @@
+//! This modules contains Copper's itemdb client
+
+use itertools::Itertools;
+use sqlx::Row;
+use std::collections::BTreeMap;
+use thiserror::Error;
+
+use crate::{
+	AttrData, AttrDataStub, AttributeId, AttributeInfo, AttributeOptions, ClassId, ItemId,
+};
+
+use super::ItemdbClient;
+use crate::{
+	client::errors::item::{CountItemsError, GetItemError, ListItemsError},
+	ItemInfo,
+};
+
+/// An error we can encounter when creating an item
+#[derive(Debug, Error)]
+pub enum AddItemError {
+	/// Database error
+	#[error("database backend error")]
+	DbError(#[from] sqlx::Error),
+
+	/// We tried to add an item to a class that doesn't exist
+	#[error("tried to add an item to a class that doesn't exist")]
+	NoSuchClass,
+
+	/// We tried to create an item that contains an
+	/// attribute that doesn't exist
+	#[error("tried to create an item an attribute that doesn't exist")]
+	BadAttribute,
+
+	/// We tried to create an item,
+	/// but provided multiple values for one attribute
+	#[error("multiple values were provided for one attribute")]
+	RepeatedAttribute,
+
+	/// We tried to assign data to an attribute,
+	/// but that data has the wrong type
+	#[error("tried to assign data to an attribute, but type doesn't match")]
+	AttributeDataTypeMismatch,
+
+	/// We tried to create an item that contains an
+	/// attribute from another class
+	#[error("tried to create an item with a foreign attribute")]
+	ForeignAttribute,
+
+	/// We tried to create an item with attribute that violate a "not null" constraint
+	#[error("tried to create an item with attributes that violate a `not null` constraint")]
+	NotNullViolated,
+
+	/// We tried to create an item with attribute that violate a "unique" constraint
+	#[error("tried to create an item with attributes that violate a `unique` constraint")]
+	UniqueViolated { conflicting_ids: Vec<ItemId> },
+}
+
+impl ItemdbClient {
+	//
+	// MARK: crud
+	//
+
+	pub async fn get_item(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		item: ItemId,
+	) -> Result<ItemInfo, GetItemError> {
+		let (id, class): (ItemId, ClassId) = {
+			let res = sqlx::query("SELECT * FROM item WHERE id=$1;")
+				.bind(i64::from(item))
+				.fetch_one(&mut **t)
+				.await;
+
+			match res {
+				Err(sqlx::Error::RowNotFound) => return Err(GetItemError::NotFound),
+				Err(e) => return Err(e.into()),
+				Ok(res) => (
+					res.get::<i64, _>("id").into(),
+					res.get::<i64, _>("class_id").into(),
+				),
+			}
+		};
+
+		let mut attribute_values: BTreeMap<AttributeId, AttrData> = BTreeMap::new();
+
+		// Fill in attributes that have data
+		// Empty attributes will be `None`.
+		let res = sqlx::query("SELECT * FROM attribute_instance WHERE item_id=$1;")
+			.bind(i64::from(item))
+			.fetch_all(&mut **t)
+			.await?;
+		for row in res {
+			let attr_id: AttributeId = row.get::<i64, _>("attribute_id").into();
+			let value: AttrData =
+				serde_json::from_str(row.get::<&str, _>("attribute_value")).unwrap();
+
+			let x = attribute_values.insert(attr_id, value);
+			assert!(x.is_none()) // Each insert should be new
+		}
+
+		Ok(ItemInfo {
+			id,
+			class,
+			attribute_values,
+		})
+	}
+
+	pub async fn list_items(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		class: ClassId,
+		skip: i64,
+		count: usize,
+	) -> Result<Vec<ItemInfo>, ListItemsError> {
+		let res = sqlx::query(
+			"
+			SELECT * FROM attribute_instance
+			WHERE item_id in (
+				SELECT id FROM item
+				WHERE class_id=$1
+				ORDER BY id
+				OFFSET $2 LIMIT $3
+			)
+			ORDER BY item_id;
+			",
+		)
+		.bind(i64::from(class))
+		.bind(skip)
+		.bind(i64::try_from(count).unwrap())
+		.fetch_all(&mut **t)
+		.await;
+		// Produces three columns:
+		// item_id, attribute_id, attribute_value
+
+		return match res {
+			Err(sqlx::Error::RowNotFound) => Err(ListItemsError::ClassNotFound),
+			Err(e) => Err(e.into()),
+			Ok(rows) => {
+				let mut out: BTreeMap<ItemId, ItemInfo> = BTreeMap::new();
+
+				for row in rows {
+					let item_id: ItemId = row.get::<i64, _>("item_id").into();
+					let attr_id: AttributeId = row.get::<i64, _>("attribute_id").into();
+					let value: AttrData =
+						serde_json::from_str(row.get::<&str, _>("attribute_value")).unwrap();
+
+					out.entry(item_id).or_insert_with(|| ItemInfo {
+						id: item_id,
+						class,
+						attribute_values: BTreeMap::new(),
+					});
+
+					let x = out.get_mut(&item_id).unwrap();
+					x.attribute_values.insert(attr_id, value);
+				}
+
+				Ok(out.into_values().collect())
+			}
+		};
+	}
+
+	pub async fn add_item(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		to_class: ClassId,
+		attributes: Vec<(AttributeId, AttrData)>,
+	) -> Result<ItemId, AddItemError> {
+		// Make sure we have at most one of each attribute
+		if !attributes.iter().map(|(x, _)| x).all_unique() {
+			return Err(AddItemError::RepeatedAttribute);
+		}
+
+		let res = sqlx::query("INSERT INTO item (class_id) VALUES ($1) RETURNING id;")
+			.bind(i64::from(to_class))
+			.fetch_one(&mut **t)
+			.await;
+
+		// Create the new item, we attach attributes afterwards
+		let new_item: ItemId = match res {
+			Ok(res) => res.get::<i64, _>("id").into(),
+			Err(sqlx::Error::Database(e)) => {
+				if e.is_foreign_key_violation() {
+					return Err(AddItemError::NoSuchClass);
+				} else {
+					return Err(sqlx::Error::Database(e).into());
+				}
+			}
+			Err(e) => return Err(e.into()),
+		};
+
+		//
+		// Create attribute instances
+		//
+
+		// Get all attributes this class has
+		let all_attrs = sqlx::query("SELECT * FROM attribute WHERE class_id=$1;")
+			.bind(i64::from(to_class))
+			.fetch_all(&mut **t)
+			.await?
+			.into_iter()
+			.map(|row| AttributeInfo {
+				id: row.get::<i64, _>("id").into(),
+				class: row.get::<i64, _>("class_id").into(),
+				order: row.get::<i64, _>("attr_order"),
+				name: row.get::<String, _>("pretty_name").into(),
+				data_type: serde_json::from_str(row.get::<&str, _>("data_type")).unwrap(),
+				options: AttributeOptions {
+					is_unique: row.get("is_unique"),
+					is_not_null: row.get("is_not_null"),
+				},
+			})
+			.collect::<Vec<_>>();
+
+		for (attr_id, _) in &attributes {
+			// Make sure all attributes we got belong to this class...
+			if all_attrs.iter().all(|x| x.id != *attr_id) {
+				return Err(AddItemError::ForeignAttribute);
+			}
+
+			// ...and that we only saw one instance of each attribute
+			if attributes.iter().filter(|(x, _)| x == attr_id).count() != 1 {
+				return Err(AddItemError::RepeatedAttribute);
+			}
+		}
+
+		// Keep track of ALL conflicts
+		// (even those across multiple attributes)
+		let mut conflicting_ids = Vec::new();
+
+		// Now, create instances for every attribute we got.
+		for attr in all_attrs.into_iter() {
+			let value = attributes
+				.iter()
+				.find(|(a_id, _)| *a_id == attr.id)
+				.map(|x| &x.1);
+
+			if let Some(value) = value {
+				// Make sure type matches
+				if value.as_stub() != attr.data_type {
+					return Err(AddItemError::AttributeDataTypeMismatch);
+				}
+
+				let value_ser = serde_json::to_string(&value).unwrap();
+
+				// Check "unique" constraint
+				// Has no effect on blobs, so don't check them.
+				// (this is why that switch is hidden in ui)
+				if attr.options.is_unique && value.as_stub() != AttrDataStub::Blob {
+					// Look for non-unique row
+					match sqlx::query(
+						"
+						SELECT item_id FROM attribute_instance
+						WHERE attribute_id=$1
+						AND attribute_value=$2
+						",
+					)
+					.bind(i64::from(attr.id))
+					.bind(&value_ser)
+					.fetch_all(&mut **t)
+					.await
+					{
+						Ok(res) => {
+							for row in res {
+								conflicting_ids.push(row.get::<i64, _>("item_id").into())
+							}
+						}
+
+						Err(e) => return Err(e.into()),
+					};
+				}
+
+				// Create the attribute instances
+				let res = sqlx::query(
+					"INSERT INTO attribute_instance (item_id, attribute_id, attribute_value)
+				VALUES ($1, $2, $3);",
+				)
+				.bind(i64::from(new_item))
+				.bind(i64::from(attr.id))
+				.bind(&value_ser)
+				.execute(&mut **t)
+				.await;
+
+				match res {
+					Ok(_) => {}
+					Err(sqlx::Error::Database(e)) => {
+						if e.is_foreign_key_violation() {
+							return Err(AddItemError::BadAttribute);
+						} else {
+							return Err(sqlx::Error::Database(e).into());
+						}
+					}
+					Err(e) => return Err(e.into()),
+				};
+			} else {
+				// Check "not null" constraint
+				if attr.options.is_not_null {
+					return Err(AddItemError::NotNullViolated);
+				}
+			}
+		}
+
+		if !conflicting_ids.is_empty() {
+			return Err(AddItemError::UniqueViolated { conflicting_ids });
+		}
+
+		return Ok(new_item);
+	}
+
+	//
+	// MARK: misc
+	//
+
+	pub async fn count_items(
+		&self,
+		t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
+		class: ClassId,
+	) -> Result<i64, CountItemsError> {
+		let res = sqlx::query("SELECT COUNT(*) FROM item WHERE class_id=$1;")
+			.bind(i64::from(class))
+			.fetch_one(&mut **t)
+			.await;
+
+		return match res {
+			Err(sqlx::Error::RowNotFound) => Err(CountItemsError::ClassNotFound),
+			Err(e) => Err(e.into()),
+			Ok(res) => Ok(res.get("count")),
+		};
+	}
+}
diff --git a/copperd/lib/itemdb/src/client/postgres/mod.rs b/copperd/lib/itemdb/src/client/client/mod.rs
similarity index 65%
rename from copperd/lib/itemdb/src/client/postgres/mod.rs
rename to copperd/lib/itemdb/src/client/client/mod.rs
index 5845a950..a63db3b4 100644
--- a/copperd/lib/itemdb/src/client/postgres/mod.rs
+++ b/copperd/lib/itemdb/src/client/client/mod.rs
@@ -1,15 +1,23 @@
+//! This modules contains Copper's itemdb client
+
 use copper_migrate::{MigrationError, Migrator};
-use sqlx::{postgres::PgPoolOptions, Connection, PgConnection, PgPool};
+use sqlx::{
+	pool::PoolConnection, postgres::PgPoolOptions, Connection, PgConnection, PgPool, Postgres,
+};
 use thiserror::Error;
 use tracing::info;
 
-mod client;
-mod helpers;
-mod migrate;
+use crate::client::migrate;
+
+mod attribute;
+mod class;
+mod dataset;
+mod item;
+pub use item::*;
 
 #[derive(Debug, Error)]
 /// An error we may encounter when connecting to postgres
-pub enum PgItemdbOpenError {
+pub enum ItemdbOpenError {
 	/// We encountered an internal database error
 	#[error("sql error")]
 	Database(#[from] sqlx::Error),
@@ -25,13 +33,13 @@ pub enum PgItemdbOpenError {
 }
 
 /// A database client for postgres
-pub struct PgItemdbClient {
+pub struct ItemdbClient {
 	pool: PgPool,
 }
 
-impl PgItemdbClient {
+impl ItemdbClient {
 	/// Create a new [`LocalDataset`].
-	pub async fn open(db_addr: &str, migrate: bool) -> Result<Self, PgItemdbOpenError> {
+	pub async fn open(db_addr: &str, migrate: bool) -> Result<Self, ItemdbOpenError> {
 		info!(message = "Opening dataset", ds_type = "postgres", ?db_addr);
 
 		// Apply migrations
@@ -39,9 +47,9 @@ impl PgItemdbClient {
 		let mut mig = Migrator::new(&mut conn, db_addr, migrate::MIGRATE_STEPS).await?;
 
 		if migrate {
-			mig.up().await.map_err(PgItemdbOpenError::Migrate)?;
+			mig.up().await.map_err(ItemdbOpenError::Migrate)?;
 		} else if !mig.is_up()? {
-			return Err(PgItemdbOpenError::NotMigrated);
+			return Err(ItemdbOpenError::NotMigrated);
 		}
 
 		drop(mig);
@@ -55,4 +63,9 @@ impl PgItemdbClient {
 
 		Ok(Self { pool })
 	}
+
+	pub async fn new_connection(&self) -> Result<PoolConnection<Postgres>, sqlx::Error> {
+		let conn = self.pool.acquire().await?;
+		return Ok(conn);
+	}
 }
diff --git a/copperd/lib/itemdb/src/client/base/errors/attribute.rs b/copperd/lib/itemdb/src/client/errors/attribute.rs
similarity index 100%
rename from copperd/lib/itemdb/src/client/base/errors/attribute.rs
rename to copperd/lib/itemdb/src/client/errors/attribute.rs
diff --git a/copperd/lib/itemdb/src/client/base/errors/class.rs b/copperd/lib/itemdb/src/client/errors/class.rs
similarity index 87%
rename from copperd/lib/itemdb/src/client/base/errors/class.rs
rename to copperd/lib/itemdb/src/client/errors/class.rs
index f962e6c5..9def3026 100644
--- a/copperd/lib/itemdb/src/client/base/errors/class.rs
+++ b/copperd/lib/itemdb/src/client/errors/class.rs
@@ -58,3 +58,13 @@ pub enum DeleteClassError {
 	#[error("database backend error")]
 	DbError(#[from] sqlx::Error),
 }
+
+/// An error we can encounter when getting a class' primary attribute
+#[derive(Debug, Error)]
+pub enum ClassPrimaryAttributeError {
+	#[error("database backend error")]
+	DbError(#[from] sqlx::Error),
+
+	#[error("class not found")]
+	NotFound,
+}
diff --git a/copperd/lib/itemdb/src/client/base/errors/dataset.rs b/copperd/lib/itemdb/src/client/errors/dataset.rs
similarity index 100%
rename from copperd/lib/itemdb/src/client/base/errors/dataset.rs
rename to copperd/lib/itemdb/src/client/errors/dataset.rs
diff --git a/copperd/lib/itemdb/src/client/base/errors/item.rs b/copperd/lib/itemdb/src/client/errors/item.rs
similarity index 100%
rename from copperd/lib/itemdb/src/client/base/errors/item.rs
rename to copperd/lib/itemdb/src/client/errors/item.rs
diff --git a/copperd/lib/itemdb/src/client/base/errors/mod.rs b/copperd/lib/itemdb/src/client/errors/mod.rs
similarity index 83%
rename from copperd/lib/itemdb/src/client/base/errors/mod.rs
rename to copperd/lib/itemdb/src/client/errors/mod.rs
index 7f8dcfb9..4684427b 100644
--- a/copperd/lib/itemdb/src/client/base/errors/mod.rs
+++ b/copperd/lib/itemdb/src/client/errors/mod.rs
@@ -4,4 +4,3 @@ pub mod attribute;
 pub mod class;
 pub mod dataset;
 pub mod item;
-pub mod transaction;
diff --git a/copperd/lib/itemdb/src/client/postgres/migrate/m_0_init.rs b/copperd/lib/itemdb/src/client/migrate/m_0_init.rs
similarity index 100%
rename from copperd/lib/itemdb/src/client/postgres/migrate/m_0_init.rs
rename to copperd/lib/itemdb/src/client/migrate/m_0_init.rs
diff --git a/copperd/lib/itemdb/src/client/postgres/migrate/mod.rs b/copperd/lib/itemdb/src/client/migrate/mod.rs
similarity index 100%
rename from copperd/lib/itemdb/src/client/postgres/migrate/mod.rs
rename to copperd/lib/itemdb/src/client/migrate/mod.rs
diff --git a/copperd/lib/itemdb/src/client/mod.rs b/copperd/lib/itemdb/src/client/mod.rs
index 18711bc2..da8b1a33 100644
--- a/copperd/lib/itemdb/src/client/mod.rs
+++ b/copperd/lib/itemdb/src/client/mod.rs
@@ -1,4 +1,9 @@
 //! This modules contains Copper's itemdb client
 
-pub mod base;
-pub mod postgres;
+#[allow(clippy::module_inception)]
+mod client;
+pub use client::*;
+
+pub mod errors;
+
+pub(crate) mod migrate;
diff --git a/copperd/lib/itemdb/src/client/postgres/client.rs b/copperd/lib/itemdb/src/client/postgres/client.rs
deleted file mode 100644
index 18efe451..00000000
--- a/copperd/lib/itemdb/src/client/postgres/client.rs
+++ /dev/null
@@ -1,732 +0,0 @@
-use std::collections::BTreeMap;
-
-use crate::{
-	client::base::errors::item::{CountItemsError, GetItemError, ListItemsError},
-	transaction::{ResultOrDirect, Transaction, TransactionAction},
-	AttrData, AttrDataStub, AttributeId, AttributeInfo, AttributeOptions, ClassId, ClassInfo,
-	DatasetId, DatasetInfo, ItemId, ItemInfo, UserId,
-};
-use async_trait::async_trait;
-use copper_util::names::check_name;
-use sqlx::{Connection, Row};
-
-use super::{helpers, PgItemdbClient};
-use crate::client::base::{
-	client::ItemdbClient,
-	errors::{
-		attribute::{
-			AddAttributeError, DeleteAttributeError, GetAttributeError, RenameAttributeError,
-		},
-		class::{AddClassError, DeleteClassError, GetClassError, RenameClassError},
-		dataset::{
-			AddDatasetError, DeleteDatasetError, GetDatasetError, ListDatasetsError,
-			RenameDatasetError,
-		},
-		transaction::ApplyTransactionError,
-	},
-};
-
-#[async_trait]
-impl ItemdbClient for PgItemdbClient {
-	//
-	// MARK: Dataset
-	//
-
-	async fn add_dataset(&self, name: &str, user: UserId) -> Result<DatasetId, AddDatasetError> {
-		match check_name(name) {
-			Ok(()) => {}
-			Err(e) => return Err(AddDatasetError::NameError(e)),
-		}
-
-		// Start transaction
-		let mut conn = self.pool.acquire().await?;
-		let mut t = conn.begin().await?;
-
-		let res =
-			sqlx::query("INSERT INTO dataset (pretty_name, owner) VALUES ($1, $2) RETURNING id;")
-				.bind(name)
-				.bind(i64::from(user))
-				.fetch_one(&mut *t)
-				.await;
-
-		t.commit().await?;
-
-		let new_handle: DatasetId = match res {
-			Ok(res) => res.get::<i64, _>("id").into(),
-			Err(sqlx::Error::Database(e)) => {
-				if e.is_unique_violation() {
-					return Err(AddDatasetError::UniqueViolation);
-				} else {
-					return Err(sqlx::Error::Database(e).into());
-				}
-			}
-			Err(e) => return Err(e.into()),
-		};
-
-		return Ok(new_handle);
-	}
-
-	async fn get_dataset(&self, dataset: DatasetId) -> Result<DatasetInfo, GetDatasetError> {
-		let mut conn = self.pool.acquire().await?;
-
-		let classes: Vec<ClassInfo> = {
-			let rows = sqlx::query("SELECT * FROM class WHERE dataset_id=$1;")
-				.bind(i64::from(dataset))
-				.fetch_all(&mut *conn)
-				.await?;
-
-			let mut classes = Vec::new();
-
-			for r in rows {
-				let class_id: ClassId = r.get::<i64, _>("id").into();
-
-				let attr_rows = sqlx::query("SELECT * FROM attribute WHERE class_id=$1;")
-					.bind(i64::from(class_id))
-					.fetch_all(&mut *conn)
-					.await?;
-
-				let attributes = attr_rows
-					.into_iter()
-					.map(|row| AttributeInfo {
-						id: row.get::<i64, _>("id").into(),
-						class: row.get::<i64, _>("id").into(),
-						order: row.get::<i64, _>("attr_order"),
-						name: row.get::<String, _>("pretty_name").into(),
-						data_type: serde_json::from_str(row.get::<&str, _>("data_type")).unwrap(),
-						options: AttributeOptions {
-							is_unique: row.get("is_unique"),
-							is_not_null: row.get("is_not_null"),
-						},
-					})
-					.collect();
-
-				let res = sqlx::query("SELECT COUNT(id) FROM item WHERE class_id=$1;")
-					.bind(i64::from(class_id))
-					.fetch_one(&mut *conn)
-					.await?;
-
-				let item_count = res.get::<i64, _>("count").try_into().unwrap();
-
-				classes.push(ClassInfo {
-					dataset,
-					id: class_id,
-					name: r.get::<String, _>("pretty_name").into(),
-					attributes,
-					item_count,
-				});
-			}
-
-			classes
-		};
-
-		let res = sqlx::query("SELECT * FROM dataset WHERE id=$1;")
-			.bind(i64::from(dataset))
-			.fetch_one(&mut *conn)
-			.await;
-
-		return match res {
-			Err(sqlx::Error::RowNotFound) => Err(GetDatasetError::NotFound),
-			Err(e) => Err(e.into()),
-			Ok(res) => Ok(DatasetInfo {
-				id: res.get::<i64, _>("id").into(),
-				owner: res.get::<i64, _>("owner").into(),
-				name: res.get::<String, _>("pretty_name").into(),
-				classes,
-			}),
-		};
-	}
-
-	async fn list_datasets(&self, owner: UserId) -> Result<Vec<DatasetInfo>, ListDatasetsError> {
-		let mut conn = self.pool.acquire().await?;
-
-		let rows = sqlx::query("SELECT * FROM dataset WHERE owner=$1;")
-			.bind(i64::from(owner))
-			.fetch_all(&mut *conn)
-			.await?;
-
-		let mut out = Vec::new();
-		for row in rows {
-			let dataset_id = row.get::<i64, _>("id").into();
-
-			let classes: Vec<ClassInfo> = {
-				let rows = sqlx::query("SELECT * FROM class WHERE dataset_id=$1;")
-					.bind(i64::from(dataset_id))
-					.fetch_all(&mut *conn)
-					.await?;
-
-				let mut classes = Vec::new();
-
-				for r in rows {
-					let class_id: ClassId = r.get::<i64, _>("id").into();
-
-					let attr_rows = sqlx::query("SELECT * FROM attribute WHERE class_id=$1;")
-						.bind(i64::from(class_id))
-						.fetch_all(&mut *conn)
-						.await?;
-
-					let attributes = attr_rows
-						.into_iter()
-						.map(|row| AttributeInfo {
-							id: row.get::<i64, _>("id").into(),
-							class: row.get::<i64, _>("id").into(),
-							order: row.get::<i64, _>("attr_order"),
-							name: row.get::<String, _>("pretty_name").into(),
-							data_type: serde_json::from_str(row.get::<&str, _>("data_type"))
-								.unwrap(),
-							options: AttributeOptions {
-								is_unique: row.get("is_unique"),
-								is_not_null: row.get("is_not_null"),
-							},
-						})
-						.collect();
-
-					let res = sqlx::query("SELECT COUNT(id) FROM item WHERE class_id=$1;")
-						.bind(i64::from(class_id))
-						.fetch_one(&mut *conn)
-						.await?;
-
-					let item_count = res.get::<i64, _>("count").try_into().unwrap();
-
-					classes.push(ClassInfo {
-						dataset: dataset_id,
-						id: class_id,
-						name: r.get::<String, _>("pretty_name").into(),
-						attributes,
-						item_count,
-					});
-				}
-
-				classes
-			};
-
-			out.push(DatasetInfo {
-				id: dataset_id,
-				owner: row.get::<i64, _>("owner").into(),
-				name: row.get::<String, _>("pretty_name").into(),
-				classes,
-			});
-		}
-
-		return Ok(out);
-	}
-
-	async fn rename_dataset(
-		&self,
-		dataset: DatasetId,
-		new_name: &str,
-	) -> Result<(), RenameDatasetError> {
-		match check_name(new_name) {
-			Ok(()) => {}
-			Err(e) => return Err(RenameDatasetError::NameError(e)),
-		}
-
-		let mut conn = self.pool.acquire().await?;
-		let mut t = conn.begin().await?;
-
-		let res = sqlx::query("UPDATE dataset SET pretty_name=$1 WHERE id=$2;")
-			.bind(new_name)
-			.bind(i64::from(dataset))
-			.execute(&mut *t)
-			.await;
-
-		t.commit().await?;
-
-		return match res {
-			Ok(_) => Ok(()),
-			Err(sqlx::Error::Database(e)) => {
-				if e.is_unique_violation() {
-					Err(RenameDatasetError::UniqueViolation)
-				} else {
-					Err(sqlx::Error::Database(e).into())
-				}
-			}
-			Err(e) => Err(e.into()),
-		};
-	}
-
-	async fn del_dataset(&self, dataset: DatasetId) -> Result<(), DeleteDatasetError> {
-		let mut conn = self.pool.acquire().await?;
-		let mut t = conn.begin().await?;
-
-		// This also deletes all attributes, etc,
-		// since they're marked with ON DELETE CASCADE.
-		sqlx::query("DELETE FROM dataset WHERE id=$1;")
-			.bind(i64::from(dataset))
-			.execute(&mut *t)
-			.await?;
-
-		t.commit().await?;
-
-		return Ok(());
-	}
-
-	//
-	// MARK: Class
-	//
-
-	async fn add_class(&self, in_dataset: DatasetId, name: &str) -> Result<ClassId, AddClassError> {
-		match check_name(name) {
-			Ok(()) => {}
-			Err(e) => return Err(AddClassError::NameError(e)),
-		}
-
-		// Start transaction
-		let mut conn = self.pool.acquire().await?;
-		let mut t = conn.begin().await?;
-
-		let res = sqlx::query(
-			"INSERT INTO class (dataset_id, pretty_name) VALUES ($1, $2) RETURNING id;",
-		)
-		.bind(i64::from(in_dataset))
-		.bind(name)
-		.fetch_one(&mut *t)
-		.await;
-
-		t.commit().await?;
-
-		let new_handle: ClassId = match res {
-			Ok(res) => res.get::<i64, _>("id").into(),
-			Err(sqlx::Error::Database(e)) => {
-				if e.is_foreign_key_violation() {
-					return Err(AddClassError::NoSuchDataset);
-				} else if e.is_unique_violation() {
-					return Err(AddClassError::UniqueViolation);
-				} else {
-					return Err(sqlx::Error::Database(e).into());
-				}
-			}
-			Err(e) => return Err(e.into()),
-		};
-		return Ok(new_handle);
-	}
-
-	async fn get_class(&self, class: ClassId) -> Result<ClassInfo, GetClassError> {
-		let mut conn = self.pool.acquire().await?;
-
-		let rows = sqlx::query("SELECT * FROM attribute WHERE class_id=$1;")
-			.bind(i64::from(class))
-			.fetch_all(&mut *conn)
-			.await?;
-
-		let attributes = rows
-			.into_iter()
-			.map(|row| AttributeInfo {
-				id: row.get::<i64, _>("id").into(),
-				class: row.get::<i64, _>("id").into(),
-				order: row.get::<i64, _>("attr_order"),
-				name: row.get::<String, _>("pretty_name").into(),
-				data_type: serde_json::from_str(row.get::<&str, _>("data_type")).unwrap(),
-				options: AttributeOptions {
-					is_unique: row.get("is_unique"),
-					is_not_null: row.get("is_not_null"),
-				},
-			})
-			.collect();
-
-		let res = sqlx::query("SELECT COUNT(id) FROM item WHERE class_id=$1;")
-			.bind(i64::from(class))
-			.fetch_one(&mut *conn)
-			.await?;
-
-		let item_count = res.get::<i64, _>("count").try_into().unwrap();
-
-		let res = sqlx::query("SELECT * FROM class WHERE id=$1;")
-			.bind(i64::from(class))
-			.fetch_one(&mut *conn)
-			.await;
-
-		return match res {
-			Err(sqlx::Error::RowNotFound) => Err(GetClassError::NotFound),
-			Err(e) => Err(e.into()),
-			Ok(res) => Ok(ClassInfo {
-				dataset: res.get::<i64, _>("dataset_id").into(),
-				id: res.get::<i64, _>("id").into(),
-				name: res.get::<String, _>("pretty_name").into(),
-				attributes,
-				item_count,
-			}),
-		};
-	}
-
-	async fn rename_class(&self, class: ClassId, new_name: &str) -> Result<(), RenameClassError> {
-		match check_name(new_name) {
-			Ok(()) => {}
-			Err(e) => return Err(RenameClassError::NameError(e)),
-		}
-
-		let mut conn = self.pool.acquire().await?;
-		let mut t = conn.begin().await?;
-
-		let res = sqlx::query("UPDATE class SET pretty_name=$1 WHERE id=$2;")
-			.bind(new_name)
-			.bind(i64::from(class))
-			.execute(&mut *t)
-			.await;
-
-		t.commit().await?;
-
-		return match res {
-			Err(sqlx::Error::Database(e)) => {
-				if e.is_unique_violation() {
-					Err(RenameClassError::UniqueViolation)
-				} else {
-					Err(sqlx::Error::Database(e).into())
-				}
-			}
-
-			Err(e) => Err(e.into()),
-
-			Ok(_) => Ok(()),
-		};
-	}
-
-	async fn del_class(&self, class: ClassId) -> Result<(), DeleteClassError> {
-		let mut conn = self.pool.acquire().await?;
-		let mut t = conn.begin().await?;
-
-		// This also deletes all classes, attributes, etc,
-		// since they're marked with ON DELETE CASCADE.
-		sqlx::query("DELETE FROM class WHERE id=$1;")
-			.bind(i64::from(class))
-			.execute(&mut *t)
-			.await?;
-
-		t.commit().await?;
-
-		return Ok(());
-	}
-
-	//
-	// MARK: Attribute
-	//
-
-	async fn add_attribute(
-		&self,
-		in_class: ClassId,
-		name: &str,
-		with_type: AttrDataStub,
-		options: AttributeOptions,
-	) -> Result<AttributeId, AddAttributeError> {
-		match check_name(name) {
-			Ok(()) => {}
-			Err(e) => return Err(AddAttributeError::NameError(e)),
-		}
-
-		// Start transaction
-		let mut conn = self.pool.acquire().await?;
-		let mut t = conn.begin().await?;
-
-		// If we're trying to create a notnull attribute,
-		// we need to ensure that no new null fields are created.
-		// ...in other words, we must make sure that no items exist.
-		if options.is_not_null {
-			let res = sqlx::query("SELECT COUNT(id) FROM item WHERE class_id=$1;")
-				.bind(i64::from(in_class))
-				.fetch_one(&mut *t)
-				.await?;
-			let item_count = res.get::<i64, _>("count");
-
-			if item_count != 0 {
-				return Err(AddAttributeError::CreatedNotNullWhenItemsExist);
-			}
-		}
-
-		let res = sqlx::query(
-			"INSERT INTO attribute(class_id, attr_order, pretty_name, data_type, is_unique, is_not_null)
-			SELECT $1, COALESCE(MAX(attr_order) + 1 , 0), $2, $3, $4, $5 FROM attribute WHERE class_id=$6
-			RETURNING id;",
-		)
-		.bind(i64::from(in_class))
-		.bind(name)
-		.bind(serde_json::to_string(&with_type).unwrap())
-		.bind(options.is_unique)
-		.bind(options.is_not_null)
-		.bind(i64::from(in_class))
-		.fetch_one(&mut *t)
-		.await;
-
-		t.commit().await?;
-
-		let new_handle: AttributeId = match res {
-			Ok(res) => res.get::<i64, _>("id").into(),
-			Err(sqlx::Error::Database(e)) => {
-				if e.is_foreign_key_violation() {
-					return Err(AddAttributeError::NoSuchClass);
-				} else if e.is_unique_violation() {
-					return Err(AddAttributeError::UniqueViolation);
-				} else {
-					return Err(sqlx::Error::Database(e).into());
-				}
-			}
-			Err(e) => return Err(e.into()),
-		};
-
-		return Ok(new_handle);
-	}
-
-	async fn get_attribute(
-		&self,
-		attribute: AttributeId,
-	) -> Result<AttributeInfo, GetAttributeError> {
-		let mut conn = self.pool.acquire().await?;
-
-		let res = sqlx::query("SELECT * FROM attribute WHERE id=$1;")
-			.bind(i64::from(attribute))
-			.fetch_one(&mut *conn)
-			.await;
-
-		return match res {
-			Err(sqlx::Error::RowNotFound) => Err(GetAttributeError::NotFound),
-			Err(e) => Err(e.into()),
-			Ok(res) => Ok(AttributeInfo {
-				id: res.get::<i64, _>("id").into(),
-				class: res.get::<i64, _>("class_id").into(),
-				order: res.get::<i64, _>("attr_order"),
-				name: res.get::<String, _>("pretty_name").into(),
-				data_type: serde_json::from_str(res.get::<&str, _>("data_type")).unwrap(),
-				options: AttributeOptions {
-					is_unique: res.get("is_unique"),
-					is_not_null: res.get("is_not_null"),
-				},
-			}),
-		};
-	}
-
-	async fn rename_attribute(
-		&self,
-		attribute: AttributeId,
-		new_name: &str,
-	) -> Result<(), RenameAttributeError> {
-		match check_name(new_name) {
-			Ok(()) => {}
-			Err(e) => return Err(RenameAttributeError::NameError(e)),
-		}
-
-		let mut conn = self.pool.acquire().await?;
-		let mut t = conn.begin().await?;
-
-		let res = sqlx::query("UPDATE attribute SET pretty_name=$1 WHERE id=$2;")
-			.bind(new_name)
-			.bind(i64::from(attribute))
-			.execute(&mut *t)
-			.await;
-
-		t.commit().await?;
-
-		return match res {
-			Ok(_) => Ok(()),
-
-			Err(sqlx::Error::Database(e)) => {
-				if e.is_unique_violation() {
-					Err(RenameAttributeError::UniqueViolation)
-				} else {
-					Err(sqlx::Error::Database(e).into())
-				}
-			}
-
-			Err(e) => Err(e.into()),
-		};
-	}
-
-	async fn del_attribute(&self, attribute: AttributeId) -> Result<(), DeleteAttributeError> {
-		let mut conn = self.pool.acquire().await?;
-		let mut t = conn.begin().await?;
-
-		// This also deletes all attribute entries, etc,
-		// since they're marked with ON DELETE CASCADE.
-		sqlx::query("DELETE FROM attribute WHERE id=$1;")
-			.bind(i64::from(attribute))
-			.execute(&mut *t)
-			.await?;
-
-		t.commit().await?;
-
-		return Ok(());
-	}
-
-	//
-	// MARK: Items
-	//
-
-	async fn get_item(&self, item: ItemId) -> Result<ItemInfo, GetItemError> {
-		let mut conn = self.pool.acquire().await?;
-
-		let (id, class): (ItemId, ClassId) = {
-			let res = sqlx::query("SELECT * FROM item WHERE id=$1;")
-				.bind(i64::from(item))
-				.fetch_one(&mut *conn)
-				.await;
-
-			match res {
-				Err(sqlx::Error::RowNotFound) => return Err(GetItemError::NotFound),
-				Err(e) => return Err(e.into()),
-				Ok(res) => (
-					res.get::<i64, _>("id").into(),
-					res.get::<i64, _>("class_id").into(),
-				),
-			}
-		};
-
-		let mut attribute_values: BTreeMap<AttributeId, AttrData> = BTreeMap::new();
-
-		// Fill in attributes that have data
-		// Empty attributes will be `None`.
-		let res = sqlx::query("SELECT * FROM attribute_instance WHERE item_id=$1;")
-			.bind(i64::from(item))
-			.fetch_all(&mut *conn)
-			.await?;
-		for row in res {
-			let attr_id: AttributeId = row.get::<i64, _>("attribute_id").into();
-			let value: AttrData =
-				serde_json::from_str(row.get::<&str, _>("attribute_value")).unwrap();
-
-			let x = attribute_values.insert(attr_id, value);
-			assert!(x.is_none()) // Each insert should be new
-		}
-
-		Ok(ItemInfo {
-			id,
-			class,
-			attribute_values,
-		})
-	}
-
-	async fn list_items(
-		&self,
-		class: ClassId,
-		skip: i64,
-		count: usize,
-	) -> Result<Vec<ItemInfo>, ListItemsError> {
-		let mut conn = self.pool.acquire().await?;
-
-		let res = sqlx::query(
-			"
-			SELECT * FROM attribute_instance
-			WHERE item_id in (
-				SELECT id FROM item
-				WHERE class_id=$1
-				ORDER BY id
-				OFFSET $2 LIMIT $3
-			)
-			ORDER BY item_id;
-			",
-		)
-		.bind(i64::from(class))
-		.bind(skip)
-		.bind(i64::try_from(count).unwrap())
-		.fetch_all(&mut *conn)
-		.await;
-		// Produces three columns:
-		// item_id, attribute_id, attribute_value
-
-		return match res {
-			Err(sqlx::Error::RowNotFound) => Err(ListItemsError::ClassNotFound),
-			Err(e) => Err(e.into()),
-			Ok(rows) => {
-				let mut out: BTreeMap<ItemId, ItemInfo> = BTreeMap::new();
-
-				for row in rows {
-					let item_id: ItemId = row.get::<i64, _>("item_id").into();
-					let attr_id: AttributeId = row.get::<i64, _>("attribute_id").into();
-					let value: AttrData =
-						serde_json::from_str(row.get::<&str, _>("attribute_value")).unwrap();
-
-					out.entry(item_id).or_insert_with(|| ItemInfo {
-						id: item_id,
-						class,
-						attribute_values: BTreeMap::new(),
-					});
-
-					let x = out.get_mut(&item_id).unwrap();
-					x.attribute_values.insert(attr_id, value);
-				}
-
-				Ok(out.into_values().collect())
-			}
-		};
-	}
-
-	async fn count_items(&self, class: ClassId) -> Result<i64, CountItemsError> {
-		let mut conn = self.pool.acquire().await?;
-
-		let res = sqlx::query("SELECT COUNT(*) FROM item WHERE class_id=$1;")
-			.bind(i64::from(class))
-			.fetch_one(&mut *conn)
-			.await;
-
-		return match res {
-			Err(sqlx::Error::RowNotFound) => Err(CountItemsError::ClassNotFound),
-			Err(e) => Err(e.into()),
-			Ok(res) => Ok(res.get("count")),
-		};
-	}
-
-	//
-	// MARK: Transaction
-	//
-
-	async fn apply_transaction(
-		&self,
-		transaction: Transaction,
-	) -> Result<(), ApplyTransactionError> {
-		// Start transaction
-		let mut conn = self.pool.acquire().await?;
-		let mut t = conn.begin().await?;
-
-		let mut transaction_results: Vec<Option<AttrData>> = Vec::new();
-
-		for action in transaction {
-			match action {
-				TransactionAction::AddItem {
-					to_class,
-					attributes,
-				} => {
-					let mut resolved_attributes = Vec::new();
-
-					// Resolve references to previous actions' results
-					for (k, v) in attributes {
-						let value = match v {
-							ResultOrDirect::Direct { value } => value,
-							ResultOrDirect::Result {
-								action_idx,
-								expected_type,
-							} => match transaction_results.get(action_idx) {
-								None => return Err(ApplyTransactionError::ReferencedBadAction),
-								Some(None) => {
-									return Err(ApplyTransactionError::ReferencedNoneResult)
-								}
-								Some(Some(x)) => {
-									if x.as_stub() != expected_type {
-										return Err(
-											ApplyTransactionError::ReferencedResultWithBadType,
-										);
-									}
-									x.clone()
-								}
-							},
-						};
-
-						resolved_attributes.push((k, value));
-					}
-
-					let res = match helpers::add_item(&mut t, to_class, resolved_attributes).await {
-						Ok(x) => x,
-						Err(x) => {
-							t.rollback().await?;
-							return Err(x.into());
-						}
-					};
-
-					transaction_results.push(Some(AttrData::Reference {
-						class: to_class,
-						item: res,
-					}))
-				}
-			};
-		}
-
-		t.commit().await?;
-
-		return Ok(());
-	}
-}
diff --git a/copperd/lib/itemdb/src/client/postgres/helpers.rs b/copperd/lib/itemdb/src/client/postgres/helpers.rs
deleted file mode 100644
index 6d34e503..00000000
--- a/copperd/lib/itemdb/src/client/postgres/helpers.rs
+++ /dev/null
@@ -1,172 +0,0 @@
-use itertools::Itertools;
-use sqlx::Row;
-
-use crate::{
-	client::base::errors::transaction::ApplyTransactionError, transaction::AddItemError, AttrData,
-	AttrDataStub, AttributeId, AttributeInfo, AttributeOptions, ClassId, ItemId,
-};
-
-pub(super) enum SqlxOrItemError {
-	Sqlx(sqlx::Error),
-	AddItem(AddItemError),
-}
-
-impl From<sqlx::Error> for SqlxOrItemError {
-	fn from(value: sqlx::Error) -> Self {
-		Self::Sqlx(value)
-	}
-}
-
-impl From<AddItemError> for SqlxOrItemError {
-	fn from(value: AddItemError) -> Self {
-		Self::AddItem(value)
-	}
-}
-
-impl From<SqlxOrItemError> for ApplyTransactionError {
-	fn from(value: SqlxOrItemError) -> Self {
-		match value {
-			SqlxOrItemError::AddItem(x) => x.into(),
-			SqlxOrItemError::Sqlx(x) => x.into(),
-		}
-	}
-}
-
-pub(super) async fn add_item(
-	t: &mut sqlx::Transaction<'_, sqlx::Postgres>,
-	to_class: ClassId,
-	attributes: Vec<(AttributeId, AttrData)>,
-) -> Result<ItemId, SqlxOrItemError> {
-	// Make sure we have at most one of each attribute
-	if !attributes.iter().map(|(x, _)| x).all_unique() {
-		return Err(AddItemError::RepeatedAttribute.into());
-	}
-
-	let res = sqlx::query("INSERT INTO item (class_id) VALUES ($1) RETURNING id;")
-		.bind(i64::from(to_class))
-		.fetch_one(&mut **t)
-		.await;
-
-	// Create the new item, we attach attributes afterwards
-	let new_item: ItemId = match res {
-		Ok(res) => res.get::<i64, _>("id").into(),
-		Err(sqlx::Error::Database(e)) => {
-			if e.is_foreign_key_violation() {
-				return Err(AddItemError::NoSuchClass.into());
-			} else {
-				return Err(sqlx::Error::Database(e).into());
-			}
-		}
-		Err(e) => return Err(e.into()),
-	};
-
-	//
-	// Create attribute instances
-	//
-
-	// Get all attributes this class has
-	let all_attrs = sqlx::query("SELECT * FROM attribute WHERE class_id=$1;")
-		.bind(i64::from(to_class))
-		.fetch_all(&mut **t)
-		.await?
-		.into_iter()
-		.map(|row| AttributeInfo {
-			id: row.get::<i64, _>("id").into(),
-			class: row.get::<i64, _>("class_id").into(),
-			order: row.get::<i64, _>("attr_order"),
-			name: row.get::<String, _>("pretty_name").into(),
-			data_type: serde_json::from_str(row.get::<&str, _>("data_type")).unwrap(),
-			options: AttributeOptions {
-				is_unique: row.get("is_unique"),
-				is_not_null: row.get("is_not_null"),
-			},
-		})
-		.collect::<Vec<_>>();
-
-	for (attr_id, _) in &attributes {
-		// Make sure all attributes we got belong to this class...
-		if all_attrs.iter().all(|x| x.id != *attr_id) {
-			return Err(SqlxOrItemError::AddItem(AddItemError::ForeignAttribute));
-		}
-
-		// ...and that we only saw one instance of each attribute
-		if attributes.iter().filter(|(x, _)| x == attr_id).count() != 1 {
-			return Err(SqlxOrItemError::AddItem(AddItemError::RepeatedAttribute));
-		}
-	}
-
-	// Now, create instances for every attribute we got.
-	for attr in all_attrs.into_iter() {
-		let value = attributes
-			.iter()
-			.find(|(a_id, _)| *a_id == attr.id)
-			.map(|x| &x.1);
-
-		if let Some(value) = value {
-			// Make sure type matches
-			if value.as_stub() != attr.data_type {
-				return Err(AddItemError::AttributeDataTypeMismatch.into());
-			}
-
-			let value_ser = serde_json::to_string(&value).unwrap();
-
-			// Check "unique" constraint
-			// Has no effect on blobs, so don't check them.
-			// (this is why that switch is hidden in ui)
-			if attr.options.is_unique && value.as_stub() != AttrDataStub::Blob {
-				// Look for non-unique row
-				match sqlx::query(
-					"
-					SELECT COUNT(*) FROM attribute_instance
-					WHERE attribute_id=$1
-					AND attribute_value=$2
-					",
-				)
-				.bind(i64::from(attr.id))
-				.bind(&value_ser)
-				.fetch_one(&mut **t)
-				.await
-				{
-					Ok(res) => {
-						let count: i64 = res.get("count");
-						if count != 0 {
-							return Err(AddItemError::UniqueViolated.into());
-						}
-					}
-
-					Err(e) => return Err(e.into()),
-				};
-			}
-
-			// Create the attribute instances
-			let res = sqlx::query(
-				"INSERT INTO attribute_instance (item_id, attribute_id, attribute_value)
-			VALUES ($1, $2, $3);",
-			)
-			.bind(i64::from(new_item))
-			.bind(i64::from(attr.id))
-			.bind(&value_ser)
-			.execute(&mut **t)
-			.await;
-
-			match res {
-				Ok(_) => {}
-				Err(sqlx::Error::Database(e)) => {
-					if e.is_foreign_key_violation() {
-						return Err(AddItemError::BadAttribute.into());
-					} else {
-						return Err(sqlx::Error::Database(e).into());
-					}
-				}
-				Err(e) => return Err(e.into()),
-			};
-		} else {
-			// Check "not null" constraint
-			if attr.options.is_not_null {
-				return Err(AddItemError::NotNullViolated.into());
-			}
-		}
-	}
-
-	return Ok(new_item);
-}
diff --git a/copperd/lib/itemdb/src/lib.rs b/copperd/lib/itemdb/src/lib.rs
index 943a34cd..28cd8f74 100644
--- a/copperd/lib/itemdb/src/lib.rs
+++ b/copperd/lib/itemdb/src/lib.rs
@@ -8,4 +8,3 @@ mod id;
 pub use id::*;
 
 pub mod client;
-pub mod transaction;
diff --git a/copperd/lib/itemdb/src/transaction.rs b/copperd/lib/itemdb/src/transaction.rs
deleted file mode 100644
index 7de021af..00000000
--- a/copperd/lib/itemdb/src/transaction.rs
+++ /dev/null
@@ -1,134 +0,0 @@
-//! Definitions for high-level dataset transactions
-use serde::{Deserialize, Serialize};
-use thiserror::Error;
-
-use crate::{AttrData, AttrDataStub, AttributeId, ClassId};
-
-//
-// MARK: Errors
-//
-
-/// An error we can encounter when creating an item
-#[derive(Debug, Serialize, Deserialize, Error)]
-pub enum AddItemError {
-	/// We tried to add an item to a class that doesn't exist
-	#[error("tried to add an item to a class that doesn't exist")]
-	NoSuchClass,
-
-	/// We tried to create an item that contains an
-	/// attribute that doesn't exist
-	#[error("tried to create an item an attribute that doesn't exist")]
-	BadAttribute,
-
-	/// We tried to create an item,
-	/// but provided multiple values for one attribute
-	#[error("multiple values were provided for one attribute")]
-	RepeatedAttribute,
-
-	/// We tried to assign data to an attribute,
-	/// but that data has the wrong type
-	#[error("tried to assign data to an attribute, but type doesn't match")]
-	AttributeDataTypeMismatch,
-
-	/// We tried to create an item that contains an
-	/// attribute from another class
-	#[error("tried to create an item with a foreign attribute")]
-	ForeignAttribute,
-
-	/// We tried to create an item with attribute that violate a "not null" constraint
-	#[error("tried to create an item with attributes that violate a `not null` constraint")]
-	NotNullViolated,
-
-	/// We tried to create an item with attribute that violate a "unique" constraint
-	#[error("tried to create an item with attributes that violate a `unique` constraint")]
-	UniqueViolated,
-}
-
-//
-// MARK: transactions
-//
-
-/// A value computed from a previous transaction,
-/// or a value provided directly.
-#[derive(Debug)]
-pub enum ResultOrDirect<T> {
-	Result {
-		action_idx: usize,
-		expected_type: AttrDataStub,
-	},
-	Direct {
-		value: T,
-	},
-}
-
-impl<T> From<T> for ResultOrDirect<T> {
-	fn from(value: T) -> Self {
-		Self::Direct { value }
-	}
-}
-
-/// A single action in a transaction
-#[derive(Debug)]
-pub enum TransactionAction {
-	/// Add an item
-	AddItem {
-		/// The class to add the item to.
-		/// The transaction will fail if this is not a valid class id.
-		to_class: ClassId,
-
-		/// The attributes to create the item with.
-		///
-		/// Each attribute may be directly provided, or
-		/// computed from the result of a previous transaction.
-		attributes: Vec<(AttributeId, ResultOrDirect<AttrData>)>,
-	},
-}
-
-impl TransactionAction {
-	pub fn result_type(&self) -> Option<AttrDataStub> {
-		match self {
-			Self::AddItem { to_class, .. } => Some(AttrDataStub::Reference { class: *to_class }),
-		}
-	}
-}
-
-/// A set of actions to apply to a dataset.
-///
-/// Transactions are atomic: they either fully succeed or fully fail.
-#[derive(Debug)]
-pub struct Transaction {
-	/// The actions to apply.
-	/// These must be applied in order.
-	actions: Vec<TransactionAction>,
-}
-
-impl Transaction {
-	pub fn new() -> Self {
-		Self {
-			actions: Vec::new(),
-		}
-	}
-
-	pub fn add_action(&mut self, action: TransactionAction) -> usize {
-		let idx = self.actions.len();
-		self.actions.push(action);
-		return idx;
-	}
-
-	pub fn is_empty(&self) -> bool {
-		return self.actions.is_empty();
-	}
-
-	pub fn len(&self) -> usize {
-		return self.actions.len();
-	}
-}
-
-impl IntoIterator for Transaction {
-	type Item = TransactionAction;
-	type IntoIter = std::vec::IntoIter<Self::Item>;
-
-	fn into_iter(self) -> Self::IntoIter {
-		return self.actions.into_iter();
-	}
-}
diff --git a/copperd/lib/jobqueue/src/base/client.rs b/copperd/lib/jobqueue/src/base/client.rs
index 41cf4d8d..88f43038 100644
--- a/copperd/lib/jobqueue/src/base/client.rs
+++ b/copperd/lib/jobqueue/src/base/client.rs
@@ -64,14 +64,6 @@ where
 	/// If this job is not `Running`, throw an error.
 	async fn fail_job_run(&self, job_id: &QueuedJobId, message: &str) -> Result<(), FailJobError>;
 
-	/// Atomically mark the given job as `FailedRunning`.
-	/// If this job is not `Running`, throw an error.
-	async fn fail_job_transaction(
-		&self,
-		job_id: &QueuedJobId,
-		message: &str,
-	) -> Result<(), FailJobError>;
-
 	/// Atomically mark the given job as `Success`.
 	/// If this job is not `Running`, throw an error.
 	async fn success_job(&self, job_id: &QueuedJobId) -> Result<(), SuccessJobError>;
diff --git a/copperd/lib/jobqueue/src/info.rs b/copperd/lib/jobqueue/src/info.rs
index 2c185c2c..502be4b9 100644
--- a/copperd/lib/jobqueue/src/info.rs
+++ b/copperd/lib/jobqueue/src/info.rs
@@ -18,7 +18,6 @@ pub enum QueuedJobState {
 	Queued,
 	Running,
 	FailedRunning { message: String },
-	FailedTransaction { message: String },
 	Success,
 }
 
diff --git a/copperd/lib/jobqueue/src/postgres/client.rs b/copperd/lib/jobqueue/src/postgres/client.rs
index 0dfd95ea..67499738 100644
--- a/copperd/lib/jobqueue/src/postgres/client.rs
+++ b/copperd/lib/jobqueue/src/postgres/client.rs
@@ -159,8 +159,7 @@ impl JobQueueClient for PgJobQueueClient {
 		.await?;
 
 		for row in res {
-			let state: QueuedJobState =
-				serde_json::from_str(row.get::<&str, _>("state")).unwrap();
+			let state: QueuedJobState = serde_json::from_str(row.get::<&str, _>("state")).unwrap();
 			let n: i64 = row.get("count");
 
 			match state {
@@ -168,7 +167,6 @@ impl JobQueueClient for PgJobQueueClient {
 				QueuedJobState::Running => counts.running_jobs += n,
 				QueuedJobState::Success { .. } => counts.successful_jobs += n,
 				QueuedJobState::FailedRunning { .. } => counts.failed_jobs += n,
-				QueuedJobState::FailedTransaction { .. } => counts.failed_jobs += n,
 				QueuedJobState::BuildError { .. } => counts.build_errors += n,
 			}
 		}
@@ -295,41 +293,6 @@ impl JobQueueClient for PgJobQueueClient {
 		};
 	}
 
-	async fn fail_job_transaction(
-		&self,
-		job_id: &QueuedJobId,
-		message: &str,
-	) -> Result<(), FailJobError> {
-		let mut conn = self.pool.acquire().await?;
-		// RETURNING id is required, RowNotFound is always thrown if it is removed.
-		let res = sqlx::query(
-			"
-			UPDATE jobs
-			SET state = $1, finished_at = $2
-			WHERE id = $3
-			AND state = $4
-			RETURNING id;
-			",
-		)
-		.bind(
-			serde_json::to_string(&QueuedJobState::FailedTransaction {
-				message: message.into(),
-			})
-			.unwrap(),
-		)
-		.bind(OffsetDateTime::now_utc())
-		.bind(job_id.as_str())
-		.bind(serde_json::to_string(&QueuedJobState::Running).unwrap())
-		.fetch_one(&mut *conn)
-		.await;
-
-		return match res {
-			Err(sqlx::Error::RowNotFound) => Err(FailJobError::NotRunning),
-			Err(e) => Err(e.into()),
-			Ok(_) => Ok(()),
-		};
-	}
-
 	async fn success_job(&self, job_id: &QueuedJobId) -> Result<(), SuccessJobError> {
 		let mut conn = self.pool.acquire().await?;
 		// RETURNING id is required, RowNotFound is always thrown if it is removed.
diff --git a/copperd/lib/piper/Cargo.toml b/copperd/lib/piper/Cargo.toml
index de30bf01..a68a3444 100644
--- a/copperd/lib/piper/Cargo.toml
+++ b/copperd/lib/piper/Cargo.toml
@@ -23,7 +23,7 @@ copper-itemdb = { workspace = true }
 thiserror = { workspace = true }
 async-trait = { workspace = true }
 serde = { workspace = true }
+sqlx = { workspace = true }
 tokio = { workspace = true }
 smartstring = { workspace = true }
 utoipa = { workspace = true }
-async-broadcast = { workspace = true }
diff --git a/copperd/lib/piper/src/base/data.rs b/copperd/lib/piper/src/base/data.rs
deleted file mode 100644
index cbca8c3d..00000000
--- a/copperd/lib/piper/src/base/data.rs
+++ /dev/null
@@ -1,29 +0,0 @@
-use std::fmt::Debug;
-
-use super::RunNodeError;
-
-/// An immutable bit of data inside a pipeline.
-///
-/// These should be easy to clone. [`PipelineData`]s that
-/// carry something big should wrap it in an [`std::sync::Arc`].
-///
-/// The [`DeserializeOwned`] implementation of this object MUST NOT be transparent.
-/// See the dispatcher param enums for more details.
-pub trait PipelineData
-where
-	Self: Debug + Clone + Send + Sync + 'static,
-{
-}
-
-pub trait PipelineJobContext<DataType: PipelineData, ResultType: PipelineJobResult>
-where
-	Self: Send + Sync + 'static,
-{
-	fn to_result(self) -> Result<ResultType, RunNodeError<DataType>>;
-}
-
-pub trait PipelineJobResult
-where
-	Self: Debug + Send + Sync + 'static,
-{
-}
diff --git a/copperd/lib/piper/src/base/dispatcher.rs b/copperd/lib/piper/src/base/dispatcher.rs
index 1800e1ad..7a95dc50 100644
--- a/copperd/lib/piper/src/base/dispatcher.rs
+++ b/copperd/lib/piper/src/base/dispatcher.rs
@@ -1,12 +1,12 @@
 use smartstring::{LazyCompact, SmartString};
-use std::{collections::BTreeMap, marker::PhantomData};
+use std::collections::BTreeMap;
 use thiserror::Error;
 
-use super::{Node, NodeParameterSpec, PipelineData, PipelineJobContext, PipelineJobResult};
+use super::{Node, NodeParameterSpec};
 
-// This type must be send + sync, since we use this inside tokio's async runtime.
-type NodeInitFnType<ResultType, DataType, ContextType> =
-	&'static (dyn Fn() -> Box<dyn Node<ResultType, DataType, ContextType>> + Send + Sync);
+pub trait NodeBuilder {
+	fn build<'ctx>(&self) -> Box<dyn Node<'ctx>>;
+}
 
 pub const INPUT_NODE_TYPE: &str = "Input";
 
@@ -19,40 +19,23 @@ pub enum RegisterNodeError {
 }
 
 /// A node type we've registered inside a [`NodeDispatcher`]
-struct RegisteredNode<
-	ResultType: PipelineJobResult,
-	DataType: PipelineData,
-	ContextType: PipelineJobContext<DataType, ResultType>,
-> {
-	_p: PhantomData<ResultType>,
-
+struct RegisteredNode {
 	/// A method that constructs a new node of this type with the provided parameters.
-	node_init: NodeInitFnType<ResultType, DataType, ContextType>,
+	builder: Box<dyn NodeBuilder>,
 
 	/// The parameters this node takes
 	_parameters: BTreeMap<SmartString<LazyCompact>, NodeParameterSpec>,
 }
 
 /// A factory struct that constructs pipeline nodes
-pub struct NodeDispatcher<
-	ResultType: PipelineJobResult,
-	DataType: PipelineData,
-	ContextType: PipelineJobContext<DataType, ResultType>,
-> {
-	_pa: PhantomData<DataType>,
-	nodes: BTreeMap<SmartString<LazyCompact>, RegisteredNode<ResultType, DataType, ContextType>>,
+pub struct NodeDispatcher {
+	nodes: BTreeMap<SmartString<LazyCompact>, RegisteredNode>,
 }
 
-impl<
-		ResultType: PipelineJobResult,
-		DataType: PipelineData,
-		ContextType: PipelineJobContext<DataType, ResultType>,
-	> NodeDispatcher<ResultType, DataType, ContextType>
-{
+impl NodeDispatcher {
 	/// Create a new [`NodeDispatcher`]
 	pub fn new() -> Self {
 		return Self {
-			_pa: PhantomData {},
 			nodes: BTreeMap::new(),
 		};
 	}
@@ -65,7 +48,7 @@ impl<
 		&mut self,
 		type_name: &str,
 		parameters: BTreeMap<SmartString<LazyCompact>, NodeParameterSpec>,
-		node_init: NodeInitFnType<ResultType, DataType, ContextType>,
+		builder: Box<dyn NodeBuilder>,
 	) -> Result<(), RegisterNodeError> {
 		if self.nodes.contains_key(type_name) || type_name == INPUT_NODE_TYPE {
 			return Err(RegisterNodeError::AlreadyExists);
@@ -74,8 +57,7 @@ impl<
 		self.nodes.insert(
 			type_name.into(),
 			RegisteredNode {
-				_p: PhantomData {},
-				node_init,
+				builder,
 				_parameters: parameters,
 			},
 		);
@@ -87,12 +69,9 @@ impl<
 		return self.nodes.contains_key(node_name);
 	}
 
-	pub fn init_node(
-		&self,
-		node_type: &str,
-	) -> Option<Box<dyn Node<ResultType, DataType, ContextType>>> {
+	pub fn init_node<'ctx>(&self, node_type: &str) -> Option<Box<dyn Node<'ctx>>> {
 		if let Some(node) = self.nodes.get(node_type) {
-			return Some((node.node_init)());
+			return Some(node.builder.build());
 		} else {
 			return None;
 		}
diff --git a/copperd/lib/piper/src/base/errors.rs b/copperd/lib/piper/src/base/errors.rs
index 0c795639..9bd307ff 100644
--- a/copperd/lib/piper/src/base/errors.rs
+++ b/copperd/lib/piper/src/base/errors.rs
@@ -1,18 +1,21 @@
 use smartstring::{LazyCompact, SmartString};
 use std::{error::Error, sync::Arc};
 use thiserror::Error;
-use tokio::{sync::mpsc, task::JoinError};
+use tokio::task::JoinError;
 
-use super::{NodeId, NodeOutput, PipelineData, PortName};
+use super::{NodeId, PortName};
 
 /// An error we encounter while running a node
 #[derive(Debug, Clone, Error)]
-pub enum RunNodeError<DataType: PipelineData> {
+pub enum RunNodeError {
 	//
 	// MARK: Errors in pipeline definition
 	//
 	//
 	//
+	#[error("database error")]
+	DbError(#[from] Arc<sqlx::Error>),
+
 	/// We expected a parameter, but it wasn't there
 	#[error("Unexpected parameter `{parameter}`")]
 	UnexpectedParameter { parameter: SmartString<LazyCompact> },
@@ -66,26 +69,10 @@ pub enum RunNodeError<DataType: PipelineData> {
 	#[error("i/o error")]
 	IoError(#[from] Arc<std::io::Error>),
 
-	/// We tried to read from a byte stream, but that stream overflowed
-	/// and we missed data. If this happens, either a node isn't reading
-	/// stream data fast enough, or our max buffer size is too small.
-	#[error("stream receiver lagged")]
-	StreamReceiverOverflowed,
-
 	/// An arbitrary error
 	#[error("generic error")]
 	Other(#[from] Arc<dyn Error + Sync + Send + 'static>),
 
-	//
-	// MARK: Critical errors
-	// (If we encounter these, our code is wrong)
-	//
-	//
-	//
-	/// We encountered a SendError while sending node output
-	#[error("error while sending output")]
-	OutputSendError(#[from] mpsc::error::SendError<NodeOutput<DataType>>),
-
 	/// A node task threw a JoinError
 	#[error("error while joining task")]
 	NodeTaskJoinError(#[from] Arc<JoinError>),
@@ -99,13 +86,19 @@ pub enum RunNodeError<DataType: PipelineData> {
 	},
 }
 
-impl<DataType: PipelineData> From<std::io::Error> for RunNodeError<DataType> {
+impl From<sqlx::Error> for RunNodeError {
+	fn from(value: sqlx::Error) -> Self {
+		Self::DbError(Arc::new(value))
+	}
+}
+
+impl From<std::io::Error> for RunNodeError {
 	fn from(value: std::io::Error) -> Self {
 		Self::IoError(Arc::new(value))
 	}
 }
 
-impl<DataType: PipelineData> From<JoinError> for RunNodeError<DataType> {
+impl From<JoinError> for RunNodeError {
 	fn from(value: JoinError) -> Self {
 		Self::NodeTaskJoinError(Arc::new(value))
 	}
diff --git a/copperd/lib/piper/src/base/mod.rs b/copperd/lib/piper/src/base/mod.rs
index e834b452..bc032ad8 100644
--- a/copperd/lib/piper/src/base/mod.rs
+++ b/copperd/lib/piper/src/base/mod.rs
@@ -1,8 +1,5 @@
 //! Interfaces for defining pipeline nodes
 
-mod data;
-pub use data::*;
-
 mod errors;
 pub use errors::*;
 
diff --git a/copperd/lib/piper/src/base/node.rs b/copperd/lib/piper/src/base/node.rs
index 01651391..5f4645f4 100644
--- a/copperd/lib/piper/src/base/node.rs
+++ b/copperd/lib/piper/src/base/node.rs
@@ -2,12 +2,9 @@ use async_trait::async_trait;
 use copper_util::graph::util::GraphNodeIdx;
 use smartstring::{LazyCompact, SmartString};
 use std::collections::BTreeMap;
-use tokio::sync::mpsc;
 
-use super::{
-	NodeId, NodeParameterValue, PipelineData, PipelineJobContext, PipelineJobResult, PortName,
-	RunNodeError,
-};
+use super::{NodeId, PortName, RunNodeError};
+use crate::{data::PipeData, helpers::NodeParameters, CopperContext};
 
 #[derive(Clone)]
 pub struct ThisNodeInfo {
@@ -16,27 +13,14 @@ pub struct ThisNodeInfo {
 	pub node_type: SmartString<LazyCompact>,
 }
 
-#[derive(Clone)]
-pub struct NodeOutput<DataType: PipelineData> {
-	pub node: ThisNodeInfo,
-	pub port: PortName,
-	pub data: Option<DataType>,
-}
-
 #[async_trait]
-pub trait Node<
-	ResultType: PipelineJobResult,
-	DataType: PipelineData,
-	ContextType: PipelineJobContext<DataType, ResultType>,
->: Sync + Send
-{
+pub trait Node<'ctx>: Sync + Send {
 	/// Run this node. TODO: document
 	async fn run(
 		&self,
-		ctx: &ContextType,
+		ctx: &CopperContext<'ctx>,
 		this_node: ThisNodeInfo,
-		params: BTreeMap<SmartString<LazyCompact>, NodeParameterValue>,
-		input: BTreeMap<PortName, Option<DataType>>,
-		output: mpsc::Sender<NodeOutput<DataType>>,
-	) -> Result<(), RunNodeError<DataType>>;
+		params: NodeParameters,
+		input: BTreeMap<PortName, Option<PipeData>>,
+	) -> Result<BTreeMap<PortName, PipeData>, RunNodeError>;
 }
diff --git a/copperd/lib/piper/src/data.rs b/copperd/lib/piper/src/data.rs
index a24c5e03..99bddd47 100644
--- a/copperd/lib/piper/src/data.rs
+++ b/copperd/lib/piper/src/data.rs
@@ -1,9 +1,9 @@
-use copper_itemdb::{AttrData, AttrDataStub};
-use copper_util::{HashType, MimeType};
+use copper_itemdb::{AttrData, ClassId, ItemId};
+use copper_util::HashType;
 use smartstring::{LazyCompact, SmartString};
-use std::{fmt::Debug, sync::Arc};
+use std::fmt::Debug;
 
-use crate::base::PipelineData;
+use crate::helpers::processor::BytesProcessorBuilder;
 
 /// Immutable bits of data inside a pipeline.
 ///
@@ -41,29 +41,17 @@ pub enum PipeData {
 	/// Arbitrary binary data.
 	/// This will be stored in the metadata db.
 	Blob {
-		/// The data
-		source: BytesSource,
+		/// The data source
+		source: BytesProcessorBuilder,
 	},
 
-	TransactionActionResult {
-		action_idx: usize,
-		result_type: AttrDataStub,
-	},
-}
+	/// A reference to an item in another class
+	Reference {
+		/// The item class this reference points to
+		class: ClassId,
 
-#[derive(Debug, Clone)]
-pub enum BytesSource {
-	Array {
-		mime: MimeType,
-		data: Arc<Vec<u8>>,
-	},
-	Stream {
-		mime: MimeType,
-		receiver: async_broadcast::Receiver<Arc<Vec<u8>>>,
-	},
-	S3 {
-		key: SmartString<LazyCompact>,
-		bucket: SmartString<LazyCompact>,
+		/// The item
+		item: ItemId,
 	},
 }
 
@@ -104,8 +92,8 @@ impl TryInto<AttrData> for PipeData {
 	fn try_into(self) -> Result<AttrData, Self::Error> {
 		return Ok(match self {
 			Self::Blob { .. } => return Err(()),
-			Self::TransactionActionResult { .. } => return Err(()),
 
+			Self::Reference { item, class } => AttrData::Reference { class, item },
 			Self::Text { value } => AttrData::Text { value },
 			Self::Boolean { value } => AttrData::Boolean { value },
 			Self::Hash { hash_type, data } => AttrData::Hash { hash_type, data },
@@ -128,5 +116,3 @@ impl TryInto<AttrData> for PipeData {
 		});
 	}
 }
-
-impl PipelineData for PipeData {}
diff --git a/copperd/lib/piper/src/helpers/mod.rs b/copperd/lib/piper/src/helpers/mod.rs
index 0ebb5c0b..1d34b6dd 100644
--- a/copperd/lib/piper/src/helpers/mod.rs
+++ b/copperd/lib/piper/src/helpers/mod.rs
@@ -1,2 +1,5 @@
-mod reader;
-pub use reader::*;
+pub mod processor;
+pub mod rawbytes;
+
+mod parameters;
+pub use parameters::*;
diff --git a/copperd/lib/piper/src/helpers/parameters.rs b/copperd/lib/piper/src/helpers/parameters.rs
new file mode 100644
index 00000000..08554e67
--- /dev/null
+++ b/copperd/lib/piper/src/helpers/parameters.rs
@@ -0,0 +1,85 @@
+use smartstring::{LazyCompact, SmartString};
+use std::collections::BTreeMap;
+
+use crate::base::{NodeParameterValue, RunNodeError};
+
+pub struct NodeParameters {
+	params: BTreeMap<SmartString<LazyCompact>, NodeParameterValue>,
+}
+
+impl From<BTreeMap<SmartString<LazyCompact>, NodeParameterValue>> for NodeParameters {
+	fn from(value: BTreeMap<SmartString<LazyCompact>, NodeParameterValue>) -> Self {
+		Self::new(value)
+	}
+}
+
+impl NodeParameters {
+	pub fn new(params: BTreeMap<SmartString<LazyCompact>, NodeParameterValue>) -> Self {
+		Self { params }
+	}
+
+	/// Return `Err(RunNodeError::UnexpectedParameter)` if we still have unhandled parameters.
+	/// Otherwise, return `Ok(())`.
+	pub fn err_if_not_empty(self) -> Result<(), RunNodeError> {
+		if let Some((param, _)) = self.params.first_key_value() {
+			return Err(RunNodeError::UnexpectedParameter {
+				parameter: param.clone(),
+			});
+		}
+
+		return Ok(());
+	}
+}
+
+impl NodeParameters {
+	pub fn pop_val(&mut self, parameter: &str) -> Result<NodeParameterValue, RunNodeError> {
+		let p = self.params.remove(parameter);
+		match p {
+			None => {
+				return Err(RunNodeError::MissingParameter {
+					parameter: parameter.into(),
+				});
+			}
+
+			Some(x) => return Ok(x),
+		}
+	}
+
+	pub fn pop_int(&mut self, parameter: &str) -> Result<i64, RunNodeError> {
+		let p = self.params.remove(parameter);
+		match p {
+			None => {
+				return Err(RunNodeError::MissingParameter {
+					parameter: parameter.into(),
+				});
+			}
+
+			Some(NodeParameterValue::Integer(x)) => return Ok(x),
+
+			Some(_) => {
+				return Err(RunNodeError::BadParameterType {
+					parameter: parameter.into(),
+				})
+			}
+		}
+	}
+
+	pub fn pop_str(&mut self, parameter: &str) -> Result<SmartString<LazyCompact>, RunNodeError> {
+		let p = self.params.remove(parameter);
+		match p {
+			None => {
+				return Err(RunNodeError::MissingParameter {
+					parameter: parameter.into(),
+				});
+			}
+
+			Some(NodeParameterValue::String(x)) => return Ok(x),
+
+			Some(_) => {
+				return Err(RunNodeError::BadParameterType {
+					parameter: parameter.into(),
+				})
+			}
+		}
+	}
+}
diff --git a/copperd/lib/piper/src/helpers/processor.rs b/copperd/lib/piper/src/helpers/processor.rs
new file mode 100644
index 00000000..0b03e061
--- /dev/null
+++ b/copperd/lib/piper/src/helpers/processor.rs
@@ -0,0 +1,150 @@
+use async_trait::async_trait;
+use copper_util::MimeType;
+use std::{fmt::Debug, sync::Arc};
+use tokio::{
+	sync::mpsc::{Receiver, Sender},
+	task::JoinSet,
+};
+
+use super::rawbytes::{RawBytesSource, RawBytesSourceReader};
+use crate::{
+	base::{NodeId, RunNodeError},
+	CopperContext,
+};
+
+/// An uninitialized [`BytesProcessor`]
+#[derive(Debug, Clone)]
+pub struct BytesProcessorBuilder {
+	/// The source of bytes to process
+	source: RawBytesSource,
+
+	/// A list of processors to run on this stream.
+	builders: Vec<Arc<dyn StreamProcessorBuilder>>,
+}
+
+unsafe impl Send for BytesProcessorBuilder {}
+unsafe impl Sync for BytesProcessorBuilder {}
+
+impl BytesProcessorBuilder {
+	pub fn new(source: RawBytesSource) -> Self {
+		Self {
+			source,
+			builders: Vec::new(),
+		}
+	}
+
+	pub fn add_processor(mut self, spb: Arc<dyn StreamProcessorBuilder>) -> Self {
+		self.builders.push(spb);
+		return self;
+	}
+
+	pub async fn build(&self, ctx: &CopperContext<'_>) -> Result<BytesProcessor, RunNodeError> {
+		let mut tasks = JoinSet::new();
+		let max_buffer_size = ctx.stream_fragment_size;
+
+		// Initial pipe
+		let (s, mut receiver) = tokio::sync::mpsc::channel(ctx.stream_channel_size);
+
+		// Start raw source reader task
+		let mut reader = RawBytesSourceReader::open(ctx, self.source.clone()).await?;
+		let mut mime = reader.mime().clone();
+		tasks.spawn(async move {
+			loop {
+				let res = reader.next_fragment(max_buffer_size).await;
+				match res {
+					Err(e) => return Err(e),
+					Ok(Some(x)) => match s.send(x).await {
+						Ok(()) => {}
+
+						// Receiver was dropped, exit early
+						Err(_) => return Ok(()),
+					},
+					Ok(None) => return Ok(()),
+				}
+			}
+		});
+
+		// Start each processor task
+		for b in &self.builders {
+			let sp = b.build();
+			mime = sp.mime().clone();
+
+			let (ns, mut nr) = tokio::sync::mpsc::channel(ctx.stream_channel_size);
+			std::mem::swap(&mut receiver, &mut nr);
+
+			tasks.spawn(async move { sp.run(nr, ns, max_buffer_size).await });
+		}
+
+		return Ok(BytesProcessor {
+			tasks,
+			receiver,
+			mime,
+		});
+	}
+}
+
+/// An initialized stream of processed bytes.
+/// This is what we use to read all byte streams.
+pub struct BytesProcessor {
+	mime: MimeType,
+	tasks: JoinSet<Result<(), RunNodeError>>,
+	receiver: Receiver<Arc<Vec<u8>>>,
+}
+
+impl BytesProcessor {
+	/// Get the type of data this processor produces
+	pub fn mime(&self) -> &MimeType {
+		&self.mime
+	}
+
+	/// Get processed data from this stream processor.
+	///
+	/// If this method returns none, this processor is closed and will never produce any more data.
+	/// If this method returns an empty vec, data is not available yet but may be available later.
+	pub async fn next_fragment(&mut self) -> Result<Option<Arc<Vec<u8>>>, RunNodeError> {
+		match self.tasks.try_join_next() {
+			None => {}
+			Some(Ok(Ok(()))) => {}
+			Some(Ok(Err(err))) => return Err(err),
+			Some(Err(err)) => return Err(err.into()),
+		}
+
+		match self.receiver.recv().await {
+			None => return Ok(None),
+			Some(x) => return Ok(Some(x)),
+		}
+	}
+}
+
+/// A helper struct that creates [`StreamProcessor`]s
+/// We need this because [`BytesSource`] will be cloned
+/// (once for each output edge) before any processors are run.
+pub trait StreamProcessorBuilder: Debug {
+	fn build(&self) -> Box<dyn StreamProcessor>;
+}
+
+/// An object that consumes one stream and produces another
+#[async_trait]
+pub trait StreamProcessor: Send + Sync {
+	/// Get the type of data this processor produces
+	fn mime(&self) -> &MimeType;
+
+	/// Get this stream processor's name
+	fn name(&self) -> &'static str;
+
+	/// Return the id of the node that created this processor
+	fn source_node_id(&self) -> &NodeId;
+
+	/// Return the type of the node that created this processor
+	fn source_node_type(&self) -> &str;
+
+	/// Run this stream processor. This is run in a separate task,
+	/// and should resolve when `source` runs out of data, or when
+	/// all possible output has been sent to `sink`.
+	async fn run(
+		&self,
+		source: Receiver<Arc<Vec<u8>>>,
+		sink: Sender<Arc<Vec<u8>>>,
+		max_buffer_size: usize,
+	) -> Result<(), RunNodeError>;
+}
diff --git a/copperd/lib/piper/src/helpers/reader.rs b/copperd/lib/piper/src/helpers/rawbytes.rs
similarity index 52%
rename from copperd/lib/piper/src/helpers/reader.rs
rename to copperd/lib/piper/src/helpers/rawbytes.rs
index 455bc119..4129b8af 100644
--- a/copperd/lib/piper/src/helpers/reader.rs
+++ b/copperd/lib/piper/src/helpers/rawbytes.rs
@@ -1,40 +1,44 @@
-use copper_itemdb::client::base::client::ItemdbClient;
 use copper_util::{s3client::S3Reader, MimeType};
+use smartstring::{LazyCompact, SmartString};
 use std::sync::Arc;
 
-use crate::{
-	base::RunNodeError,
-	data::{BytesSource, PipeData},
-	CopperContext,
-};
+use crate::{base::RunNodeError, CopperContext};
 
-pub enum BytesSourceReader {
+/// An unprocessed source of binary data
+#[derive(Debug, Clone)]
+pub enum RawBytesSource {
 	Array {
-		data: Option<Arc<Vec<u8>>>,
 		mime: MimeType,
+		data: Arc<Vec<u8>>,
 	},
 
-	Stream {
-		receiver: async_broadcast::Receiver<Arc<Vec<u8>>>,
+	S3 {
+		key: SmartString<LazyCompact>,
+		bucket: SmartString<LazyCompact>,
+	},
+}
+
+pub(crate) enum RawBytesSourceReader {
+	Array {
+		data: Option<Arc<Vec<u8>>>,
 		mime: MimeType,
 	},
+
 	S3(S3Reader),
 }
 
-impl BytesSourceReader {
-	pub async fn open<Itemdb: ItemdbClient>(
-		ctx: &CopperContext<Itemdb>,
-		source: BytesSource,
-	) -> Result<Self, RunNodeError<PipeData>> {
+impl RawBytesSourceReader {
+	pub async fn open(
+		ctx: &CopperContext<'_>,
+		source: RawBytesSource,
+	) -> Result<Self, RunNodeError> {
 		return Ok(match source {
-			BytesSource::Array { data, mime } => Self::Array {
+			RawBytesSource::Array { data, mime } => Self::Array {
 				data: Some(data),
 				mime,
 			},
 
-			BytesSource::Stream { receiver, mime } => Self::Stream { receiver, mime },
-
-			BytesSource::S3 { bucket, key } => Self::S3(
+			RawBytesSource::S3 { bucket, key } => Self::S3(
 				ctx.objectstore_client
 					.create_reader(&bucket, &key)
 					.await
@@ -45,7 +49,7 @@ impl BytesSourceReader {
 
 	pub fn mime(&self) -> &MimeType {
 		match self {
-			Self::Stream { mime, .. } | Self::Array { mime, .. } => mime,
+			Self::Array { mime, .. } => mime,
 			Self::S3(reader) => reader.mime(),
 		}
 	}
@@ -55,20 +59,10 @@ impl BytesSourceReader {
 	pub async fn next_fragment(
 		&mut self,
 		max_buffer_size: usize,
-	) -> Result<Option<Arc<Vec<u8>>>, RunNodeError<PipeData>> {
+	) -> Result<Option<Arc<Vec<u8>>>, RunNodeError> {
 		match self {
 			Self::Array { data, .. } => return Ok(data.take()),
 
-			Self::Stream { receiver, .. } => {
-				match receiver.recv().await {
-					Ok(x) => return Ok(Some(x)),
-					Err(async_broadcast::RecvError::Closed) => return Ok(None),
-					Err(async_broadcast::RecvError::Overflowed(_)) => {
-						return Err(RunNodeError::StreamReceiverOverflowed)
-					}
-				};
-			}
-
 			Self::S3(reader) => {
 				if reader.is_done() {
 					return Ok(None);
diff --git a/copperd/lib/piper/src/lib.rs b/copperd/lib/piper/src/lib.rs
index aacff0c6..9ae93eb7 100644
--- a/copperd/lib/piper/src/lib.rs
+++ b/copperd/lib/piper/src/lib.rs
@@ -3,26 +3,20 @@ pub mod data;
 pub mod helpers;
 pub mod json;
 
-use base::{PipelineJobContext, PipelineJobResult, RunNodeError};
-use copper_itemdb::{client::base::client::ItemdbClient, transaction::Transaction, UserId};
+use copper_itemdb::{client::ItemdbClient, UserId};
 use copper_util::s3client::S3Client;
-use data::PipeData;
 use smartstring::{LazyCompact, SmartString};
+use sqlx::{Postgres, Transaction};
 use std::sync::Arc;
 use tokio::sync::Mutex;
 
-pub struct CopperContext<Itemdb: ItemdbClient + 'static> {
+pub struct CopperContext<'a> {
 	/// The fragment size, in bytes, in which we should read large blobs.
 	///
 	/// A larger value uses more memory, but increases performance
 	/// (with diminishing returns)
-	pub blob_fragment_size: usize,
-
-	/// The message capacity of binary stream channels.
-	///
-	/// Smaller values increase the probability of pipeline runs failing due to an
-	/// overflowing channel, larger values use more memory.
-	pub stream_channel_capacity: usize,
+	pub stream_fragment_size: usize,
+	pub stream_channel_size: usize,
 
 	/// The id of this job
 	pub job_id: SmartString<LazyCompact>,
@@ -33,7 +27,7 @@ pub struct CopperContext<Itemdb: ItemdbClient + 'static> {
 	pub run_by_user: UserId,
 
 	/// The itemdb client this runner should use
-	pub itemdb_client: Arc<Itemdb>,
+	pub itemdb_client: Arc<ItemdbClient>,
 
 	/// The objectstore client this pipeline should use
 	pub objectstore_client: Arc<S3Client>,
@@ -41,23 +35,9 @@ pub struct CopperContext<Itemdb: ItemdbClient + 'static> {
 	/// The name of the bucket to store blobs in
 	pub objectstore_blob_bucket: SmartString<LazyCompact>,
 
-	/// The transaction to apply once this pipeline successfully resolves.
-	/// A pipeline triggers AT MOST one transaction.
-	pub transaction: Mutex<Transaction>,
-}
-
-#[derive(Debug)]
-pub struct JobRunResult {
-	pub transaction: Transaction,
-}
-
-impl PipelineJobResult for JobRunResult {}
-
-impl<Itemdb: ItemdbClient + 'static> PipelineJobContext<PipeData, JobRunResult>
-	for CopperContext<Itemdb>
-{
-	fn to_result(self) -> Result<JobRunResult, RunNodeError<PipeData>> {
-		let transaction = self.transaction.into_inner();
-		return Ok(JobRunResult { transaction });
-	}
+	/// The transaction we'll use to query the item db
+	///
+	/// This makes sure pipelines are atomic.
+	/// We `.commit()` only if the pipeline runs successfully.
+	pub item_db_transaction: Mutex<Transaction<'a, Postgres>>,
 }
diff --git a/copperd/nodes/audiofile/Cargo.toml b/copperd/nodes/audiofile/Cargo.toml
index 45eeaf89..f48cd37b 100644
--- a/copperd/nodes/audiofile/Cargo.toml
+++ b/copperd/nodes/audiofile/Cargo.toml
@@ -19,16 +19,14 @@ workspace = true
 [dependencies]
 copper-util = { workspace = true }
 copper-piper = { workspace = true }
-copper-itemdb = { workspace = true }
 
+tokio = { workspace = true }
 tracing = { workspace = true }
 thiserror = { workspace = true }
 smartstring = { workspace = true }
 serde_with = { workspace = true }
-tokio = { workspace = true }
 base64 = { workspace = true }
 async-trait = { workspace = true }
-async-broadcast = { workspace = true }
 
 [dev-dependencies]
 sha2 = { workspace = true }
diff --git a/copperd/nodes/audiofile/src/nodes/extractcovers.rs b/copperd/nodes/audiofile/src/nodes/extractcovers.rs
index 2da73b00..ad57906e 100644
--- a/copperd/nodes/audiofile/src/nodes/extractcovers.rs
+++ b/copperd/nodes/audiofile/src/nodes/extractcovers.rs
@@ -1,39 +1,36 @@
 use crate::flac::proc::pictures::FlacPictureReader;
 use async_trait::async_trait;
-use copper_itemdb::client::base::client::ItemdbClient;
 use copper_piper::{
-	base::{Node, NodeOutput, NodeParameterValue, PortName, RunNodeError, ThisNodeInfo},
-	data::{BytesSource, PipeData},
-	helpers::BytesSourceReader,
-	CopperContext, JobRunResult,
+	base::{Node, NodeBuilder, PortName, RunNodeError, ThisNodeInfo},
+	data::PipeData,
+	helpers::{processor::BytesProcessorBuilder, rawbytes::RawBytesSource, NodeParameters},
+	CopperContext,
 };
-use smartstring::{LazyCompact, SmartString};
 use std::{collections::BTreeMap, sync::Arc};
-use tokio::sync::mpsc;
 use tracing::{debug, trace};
 
 pub struct ExtractCovers {}
 
+impl NodeBuilder for ExtractCovers {
+	fn build<'ctx>(&self) -> Box<dyn Node<'ctx>> {
+		Box::new(Self {})
+	}
+}
+
 // Inputs: "data" - Bytes
-// Outputs: variable, depends on tags
 #[async_trait]
-impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> for ExtractCovers {
+impl<'ctx> Node<'ctx> for ExtractCovers {
 	async fn run(
 		&self,
-		ctx: &CopperContext<Itemdb>,
+		ctx: &CopperContext<'ctx>,
 		this_node: ThisNodeInfo,
-		params: BTreeMap<SmartString<LazyCompact>, NodeParameterValue>,
+		params: NodeParameters,
 		mut input: BTreeMap<PortName, Option<PipeData>>,
-		output: mpsc::Sender<NodeOutput<PipeData>>,
-	) -> Result<(), RunNodeError<PipeData>> {
+	) -> Result<BTreeMap<PortName, PipeData>, RunNodeError> {
 		//
 		// Extract parameters
 		//
-		if let Some((param, _)) = params.first_key_value() {
-			return Err(RunNodeError::UnexpectedParameter {
-				parameter: param.clone(),
-			});
-		}
+		params.err_if_not_empty()?;
 
 		//
 		// Extract arguments
@@ -60,7 +57,7 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 				})
 			}
 
-			Some(PipeData::Blob { source, .. }) => BytesSourceReader::open(ctx, source).await?,
+			Some(PipeData::Blob { source, .. }) => source.build(ctx).await?,
 
 			_ => {
 				return Err(RunNodeError::BadInputType {
@@ -78,7 +75,7 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 		);
 		let mut picreader = FlacPictureReader::new();
 
-		while let Some(data) = reader.next_fragment(ctx.blob_fragment_size).await? {
+		while let Some(data) = reader.next_fragment().await? {
 			picreader
 				.push_data(&data)
 				.map_err(|e| RunNodeError::Other(Arc::new(e)))?;
@@ -91,6 +88,9 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 		//
 		// Send the first cover we find
 		//
+
+		let mut output = BTreeMap::new();
+
 		if let Some(picture) = picreader.pop_picture() {
 			debug!(
 				message = "Found a cover, sending",
@@ -98,33 +98,22 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 				picture = ?picture
 			);
 
-			output
-				.send(NodeOutput {
-					node: this_node,
-					port: PortName::new("cover_data"),
-					data: Some(PipeData::Blob {
-						source: BytesSource::Array {
-							mime: picture.mime.clone(),
-							data: Arc::new(picture.img_data),
-						},
+			output.insert(
+				PortName::new("cover_data"),
+				PipeData::Blob {
+					source: BytesProcessorBuilder::new(RawBytesSource::Array {
+						mime: picture.mime.clone(),
+						data: Arc::new(picture.img_data),
 					}),
-				})
-				.await?;
+				},
+			);
 		} else {
 			debug!(
 				message = "Did not find a cover, sending None",
 				node_id = ?this_node.id
 			);
-
-			output
-				.send(NodeOutput {
-					node: this_node,
-					port: PortName::new("cover_data"),
-					data: None,
-				})
-				.await?;
 		}
 
-		return Ok(());
+		return Ok(output);
 	}
 }
diff --git a/copperd/nodes/audiofile/src/nodes/extracttags.rs b/copperd/nodes/audiofile/src/nodes/extracttags.rs
index 90d02980..370c17aa 100644
--- a/copperd/nodes/audiofile/src/nodes/extracttags.rs
+++ b/copperd/nodes/audiofile/src/nodes/extracttags.rs
@@ -3,39 +3,44 @@ use crate::{
 	flac::blockread::{FlacBlock, FlacBlockReader, FlacBlockSelector},
 };
 use async_trait::async_trait;
-use copper_itemdb::client::base::client::ItemdbClient;
 use copper_piper::{
-	base::{Node, NodeOutput, NodeParameterValue, PortName, RunNodeError, ThisNodeInfo},
+	base::{Node, NodeBuilder, NodeParameterValue, PortName, RunNodeError, ThisNodeInfo},
 	data::PipeData,
-	helpers::BytesSourceReader,
-	CopperContext, JobRunResult,
+	helpers::NodeParameters,
+	CopperContext,
 };
-use smartstring::{LazyCompact, SmartString};
 use std::{collections::BTreeMap, sync::Arc};
-use tokio::sync::mpsc;
 use tracing::{debug, trace};
 
 /// Extract tags from audio metadata
 pub struct ExtractTags {}
 
+impl NodeBuilder for ExtractTags {
+	fn build<'ctx>(&self) -> Box<dyn Node<'ctx>> {
+		Box::new(Self {})
+	}
+}
+
 // Inputs: "data" - Bytes
 // Outputs: variable, depends on tags
 #[async_trait]
-impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> for ExtractTags {
+impl<'ctx> Node<'ctx> for ExtractTags {
 	async fn run(
 		&self,
-		ctx: &CopperContext<Itemdb>,
+		ctx: &CopperContext<'ctx>,
 		this_node: ThisNodeInfo,
-		mut params: BTreeMap<SmartString<LazyCompact>, NodeParameterValue>,
+		mut params: NodeParameters,
 		mut input: BTreeMap<PortName, Option<PipeData>>,
-		output: mpsc::Sender<NodeOutput<PipeData>>,
-	) -> Result<(), RunNodeError<PipeData>> {
+	) -> Result<BTreeMap<PortName, PipeData>, RunNodeError> {
 		//
 		// Extract parameters
 		//
-		let mut tags: BTreeMap<PortName, TagType> = BTreeMap::new();
-		if let Some(taglist) = params.remove("tags") {
-			match taglist {
+
+		let tags = {
+			let mut tags: BTreeMap<PortName, TagType> = BTreeMap::new();
+			let val = params.pop_val("tags")?;
+
+			match val {
 				NodeParameterValue::List(list) => {
 					for t in list {
 						match t {
@@ -55,18 +60,12 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 						parameter: "tags".into(),
 					})
 				}
-			}
-		} else {
-			return Err(RunNodeError::MissingParameter {
-				parameter: "tags".into(),
-			});
-		}
+			};
 
-		if let Some((param, _)) = params.first_key_value() {
-			return Err(RunNodeError::UnexpectedParameter {
-				parameter: param.clone(),
-			});
-		}
+			tags
+		};
+
+		params.err_if_not_empty()?;
 
 		//
 		// Extract arguments
@@ -93,7 +92,7 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 				})
 			}
 
-			Some(PipeData::Blob { source, .. }) => BytesSourceReader::open(ctx, source).await?,
+			Some(PipeData::Blob { source, .. }) => source.build(ctx).await?,
 
 			_ => {
 				return Err(RunNodeError::BadInputType {
@@ -115,7 +114,7 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 			..Default::default()
 		});
 
-		while let Some(data) = reader.next_fragment(ctx.blob_fragment_size).await? {
+		while let Some(data) = reader.next_fragment().await? {
 			block_reader
 				.push_data(&data)
 				.map_err(|e| RunNodeError::Other(Arc::new(e)))?;
@@ -128,6 +127,9 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 		//
 		// Return tags
 		//
+
+		let mut output = BTreeMap::new();
+
 		while block_reader.has_block() {
 			let b = block_reader.pop_block().unwrap();
 			match b {
@@ -136,23 +138,15 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 						if let Some((_, tag_value)) =
 							comment.comment.comments.iter().find(|(t, _)| t == tag_type)
 						{
-							output
-								.send(NodeOutput {
-									node: this_node.clone(),
-									port: port.clone(),
-									data: Some(PipeData::Text {
-										value: tag_value.clone(),
-									}),
-								})
-								.await?;
-						} else {
-							output
-								.send(NodeOutput {
-									node: this_node.clone(),
-									port: port.clone(),
-									data: None,
-								})
-								.await?;
+							let x = output.insert(
+								port.clone(),
+								PipeData::Text {
+									value: tag_value.clone(),
+								},
+							);
+
+							// Each insertion should be new
+							assert!(x.is_none());
 						}
 					}
 				}
@@ -165,6 +159,6 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 			assert!(!block_reader.has_block());
 		}
 
-		return Ok(());
+		return Ok(output);
 	}
 }
diff --git a/copperd/nodes/audiofile/src/nodes/mod.rs b/copperd/nodes/audiofile/src/nodes/mod.rs
index 88738637..30078748 100644
--- a/copperd/nodes/audiofile/src/nodes/mod.rs
+++ b/copperd/nodes/audiofile/src/nodes/mod.rs
@@ -1,11 +1,5 @@
 //! Pipeline nodes for processing audio files
-
-use copper_itemdb::client::base::client::ItemdbClient;
-use copper_piper::{
-	base::{NodeDispatcher, RegisterNodeError},
-	data::PipeData,
-	CopperContext, JobRunResult,
-};
+use copper_piper::base::{NodeDispatcher, RegisterNodeError};
 use std::collections::BTreeMap;
 
 mod extractcovers;
@@ -13,25 +7,29 @@ mod extracttags;
 mod striptags;
 
 /// Register all nodes in this module into the given dispatcher
-pub fn register<Itemdb: ItemdbClient>(
-	dispatcher: &mut NodeDispatcher<JobRunResult, PipeData, CopperContext<Itemdb>>,
-) -> Result<(), RegisterNodeError> {
+pub fn register(dispatcher: &mut NodeDispatcher) -> Result<(), RegisterNodeError> {
 	dispatcher
-		.register_node("StripTags", BTreeMap::new(), &|| {
-			Box::new(striptags::StripTags {})
-		})
+		.register_node(
+			"StripTags",
+			BTreeMap::new(),
+			Box::new(striptags::StripTags {}),
+		)
 		.unwrap();
 
 	dispatcher
-		.register_node("ExtractCovers", BTreeMap::new(), &|| {
-			Box::new(extractcovers::ExtractCovers {})
-		})
+		.register_node(
+			"ExtractCovers",
+			BTreeMap::new(),
+			Box::new(extractcovers::ExtractCovers {}),
+		)
 		.unwrap();
 
 	dispatcher
-		.register_node("ExtractTags", BTreeMap::new(), &|| {
-			Box::new(extracttags::ExtractTags {})
-		})
+		.register_node(
+			"ExtractTags",
+			BTreeMap::new(),
+			Box::new(extracttags::ExtractTags {}),
+		)
 		.unwrap();
 
 	return Ok(());
diff --git a/copperd/nodes/audiofile/src/nodes/striptags.rs b/copperd/nodes/audiofile/src/nodes/striptags.rs
index da3327fc..24ec31ff 100644
--- a/copperd/nodes/audiofile/src/nodes/striptags.rs
+++ b/copperd/nodes/audiofile/src/nodes/striptags.rs
@@ -2,42 +2,45 @@
 
 use crate::flac::proc::metastrip::FlacMetaStrip;
 use async_trait::async_trait;
-use copper_itemdb::client::base::client::ItemdbClient;
 use copper_piper::{
-	base::{Node, NodeOutput, NodeParameterValue, PortName, RunNodeError, ThisNodeInfo},
-	data::{BytesSource, PipeData},
-	helpers::BytesSourceReader,
-	CopperContext, JobRunResult,
+	base::{Node, NodeBuilder, NodeId, PortName, RunNodeError, ThisNodeInfo},
+	data::PipeData,
+	helpers::{
+		processor::{StreamProcessor, StreamProcessorBuilder},
+		NodeParameters,
+	},
+	CopperContext,
 };
 use copper_util::MimeType;
 use smartstring::{LazyCompact, SmartString};
 use std::{collections::BTreeMap, sync::Arc};
-use tokio::sync::mpsc;
-use tracing::{debug, trace};
+use tokio::sync::mpsc::{Receiver, Sender};
+use tracing::debug;
 
 /// Strip all metadata from an audio file
 pub struct StripTags {}
 
+impl NodeBuilder for StripTags {
+	fn build<'ctx>(&self) -> Box<dyn Node<'ctx>> {
+		Box::new(Self {})
+	}
+}
+
 // Input: "data" - Blob
 // Output: "out" - Blob
 #[async_trait]
-impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> for StripTags {
+impl<'ctx> Node<'ctx> for StripTags {
 	async fn run(
 		&self,
-		ctx: &CopperContext<Itemdb>,
+		_ctx: &CopperContext<'ctx>,
 		this_node: ThisNodeInfo,
-		params: BTreeMap<SmartString<LazyCompact>, NodeParameterValue>,
+		params: NodeParameters,
 		mut input: BTreeMap<PortName, Option<PipeData>>,
-		output: mpsc::Sender<NodeOutput<PipeData>>,
-	) -> Result<(), RunNodeError<PipeData>> {
+	) -> Result<BTreeMap<PortName, PipeData>, RunNodeError> {
 		//
 		// Extract parameters
 		//
-		if let Some((param, _)) = params.first_key_value() {
-			return Err(RunNodeError::UnexpectedParameter {
-				parameter: param.clone(),
-			});
-		}
+		params.err_if_not_empty()?;
 
 		//
 		// Extract arguments
@@ -52,14 +55,14 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 			return Err(RunNodeError::UnrecognizedInput { port });
 		}
 
-		let mut reader = match data.unwrap() {
+		let source = match data.unwrap() {
 			None => {
 				return Err(RunNodeError::RequiredInputNull {
 					port: PortName::new("data"),
 				})
 			}
 
-			Some(PipeData::Blob { source, .. }) => BytesSourceReader::open(ctx, source).await?,
+			Some(PipeData::Blob { source, .. }) => source,
 
 			_ => {
 				return Err(RunNodeError::BadInputType {
@@ -68,39 +71,72 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 			}
 		};
 
-		//
-		// Send output handle
-		//
-		let (tx, rx) = async_broadcast::broadcast(ctx.stream_channel_capacity);
-		output
-			.send(NodeOutput {
-				node: this_node.clone(),
-				port: PortName::new("out"),
-				data: Some(PipeData::Blob {
-					source: BytesSource::Stream {
-						mime: MimeType::Flac,
-						receiver: rx,
-					},
-				}),
-			})
-			.await?;
-
 		debug!(
 			message = "Setup done, stripping tags",
 			node_id = ?this_node.id
 		);
 
+		let mut output = BTreeMap::new();
+
+		output.insert(
+			PortName::new("out"),
+			PipeData::Blob {
+				source: source.add_processor(Arc::new(TagStripProcessor {
+					node_id: this_node.id.clone(),
+					node_type: this_node.node_type.clone(),
+				})),
+			},
+		);
+
+		return Ok(output);
+	}
+}
+
+#[derive(Debug, Clone)]
+struct TagStripProcessor {
+	node_id: NodeId,
+	node_type: SmartString<LazyCompact>,
+}
+
+impl StreamProcessorBuilder for TagStripProcessor {
+	fn build(&self) -> Box<dyn StreamProcessor> {
+		Box::new(self.clone())
+	}
+}
+
+#[async_trait]
+impl StreamProcessor for TagStripProcessor {
+	fn mime(&self) -> &MimeType {
+		return &MimeType::Flac;
+	}
+
+	fn name(&self) -> &'static str {
+		"TagStripProcessor"
+	}
+
+	fn source_node_id(&self) -> &NodeId {
+		&self.node_id
+	}
+
+	/// Return the type of the node that created this processor
+	fn source_node_type(&self) -> &str {
+		&self.node_type
+	}
+
+	async fn run(
+		&self,
+		mut source: Receiver<Arc<Vec<u8>>>,
+		sink: Sender<Arc<Vec<u8>>>,
+		max_buffer_size: usize,
+	) -> Result<(), RunNodeError> {
 		//
 		// Strip tags
 		//
-		debug!(
-			message = "Stripping tags",
-			node_id = ?this_node.id
-		);
+
 		let mut strip = FlacMetaStrip::new();
 		let mut out_bytes = Vec::new();
 
-		while let Some(data) = reader.next_fragment(ctx.blob_fragment_size).await? {
+		while let Some(data) = source.recv().await {
 			strip
 				.push_data(&data)
 				.map_err(|e| RunNodeError::Other(Arc::new(e)))?;
@@ -109,26 +145,16 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 				.read_data(&mut out_bytes)
 				.map_err(|e| RunNodeError::Other(Arc::new(e)))?;
 
-			if out_bytes.len() >= ctx.blob_fragment_size {
+			if out_bytes.len() >= max_buffer_size {
 				let x = std::mem::take(&mut out_bytes);
-				trace!(
-					message = "Sending bytes",
-					n_bytes = x.len(),
-					node_id = ?this_node.id
-				);
-
-				match tx.broadcast(Arc::new(x)).await {
-					Ok(_) => {}
-
-					// Exit early if no receivers exist
-					Err(async_broadcast::SendError(_)) => {
-						debug!(
-							message = "Byte sender is closed, exiting early",
-							node_id = ?this_node.id
-						);
-						return Ok(());
-					}
-				}
+
+				match sink.send(Arc::new(x)).await {
+					Ok(()) => {}
+
+					// Not an error, our receiver was dropped.
+					// Exit early if that happens!
+					Err(_) => return Ok(()),
+				};
 			}
 		}
 
@@ -142,24 +168,13 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 				.map_err(|e| RunNodeError::Other(Arc::new(e)))?;
 		}
 
-		trace!(
-			message = "Sending final bytes",
-			n_bytes = out_bytes.len(),
-			node_id = ?this_node.id
-		);
-
-		match tx.broadcast(Arc::new(out_bytes)).await {
-			Ok(_) => {}
+		match sink.send(Arc::new(out_bytes)).await {
+			Ok(()) => {}
 
-			// Exit early if no receivers exist
-			Err(async_broadcast::SendError(_)) => {
-				debug!(
-					message = "Byte sender is closed, exiting early",
-					node_id = ?this_node.id
-				);
-				return Ok(());
-			}
-		}
+			// Not an error, our receiver was dropped.
+			// Exit early if that happens!
+			Err(_) => return Ok(()),
+		};
 
 		return Ok(());
 	}
diff --git a/copperd/nodes/basic/Cargo.toml b/copperd/nodes/basic/Cargo.toml
index a271e378..08c0f83c 100644
--- a/copperd/nodes/basic/Cargo.toml
+++ b/copperd/nodes/basic/Cargo.toml
@@ -22,10 +22,10 @@ copper-piper = { workspace = true }
 copper-itemdb = { workspace = true }
 
 rand = { workspace = true }
+sqlx = { workspace = true }
 tracing = { workspace = true }
 tokio = { workspace = true }
 async-trait = { workspace = true }
 smartstring = { workspace = true }
 sha2 = { workspace = true }
 md5 = { workspace = true }
-serde_json = { workspace = true }
diff --git a/copperd/nodes/basic/src/additem.rs b/copperd/nodes/basic/src/additem.rs
index f30dc4f9..d65f9222 100644
--- a/copperd/nodes/basic/src/additem.rs
+++ b/copperd/nodes/basic/src/additem.rs
@@ -1,114 +1,116 @@
 use async_trait::async_trait;
 use copper_itemdb::{
-	client::base::{
-		client::ItemdbClient,
+	client::{
 		errors::{class::GetClassError, dataset::GetDatasetError},
+		AddItemError,
 	},
-	transaction::{ResultOrDirect, TransactionAction},
-	AttrData, AttributeInfo, ClassInfo,
+	AttrData, AttributeInfo,
 };
 use copper_piper::{
-	base::{Node, NodeOutput, NodeParameterValue, PortName, RunNodeError, ThisNodeInfo},
+	base::{Node, NodeBuilder, PortName, RunNodeError, ThisNodeInfo},
 	data::PipeData,
-	helpers::BytesSourceReader,
-	CopperContext, JobRunResult,
+	helpers::NodeParameters,
+	CopperContext,
 };
 use rand::{distributions::Alphanumeric, Rng};
 use smartstring::{LazyCompact, SmartString};
+use sqlx::Acquire;
 use std::{collections::BTreeMap, sync::Arc};
-use tokio::sync::mpsc;
 use tracing::{debug, trace};
 
+/// How we should react when we try to create a node that
+/// violates a "unique" constraint
+enum OnUniqueViolation {
+	/// Throw an error & cancel the pipeline
+	Fail,
+
+	/// If there is ONE conflicting item, create nothing and return its id.
+	/// If more than one item conflicts, error.
+	Select,
+}
+
 pub struct AddItem {}
 
+impl NodeBuilder for AddItem {
+	fn build<'ctx>(&self) -> Box<dyn Node<'ctx>> {
+		Box::new(Self {})
+	}
+}
+
 // Inputs: depends on class
-// Outputs: None
+// Outputs: new_item: reference to new item
 #[async_trait]
-impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> for AddItem {
+impl<'ctx> Node<'ctx> for AddItem {
 	async fn run(
 		&self,
-		ctx: &CopperContext<Itemdb>,
-		this_node: ThisNodeInfo,
-		mut params: BTreeMap<SmartString<LazyCompact>, NodeParameterValue>,
+		ctx: &CopperContext<'ctx>,
+		_this_node: ThisNodeInfo,
+		mut params: NodeParameters,
 		mut input: BTreeMap<PortName, Option<PipeData>>,
-		output: mpsc::Sender<NodeOutput<PipeData>>,
-	) -> Result<(), RunNodeError<PipeData>> {
+	) -> Result<BTreeMap<PortName, PipeData>, RunNodeError> {
+		let mut trans = ctx.item_db_transaction.lock().await;
+
 		//
 		// Extract parameters
 		//
-		let class: ClassInfo = if let Some(value) = params.remove("class") {
-			match value {
-				NodeParameterValue::Integer(x) => ctx
-					.itemdb_client
-					.get_class(x.into())
-					.await
-					.map_err(|e| match e {
-						GetClassError::NotFound => RunNodeError::BadParameterOther {
-							parameter: "class".into(),
-							message: "this class doesn't exist".into(),
-						},
-						_ => RunNodeError::Other(Arc::new(e)),
-					})?,
-
-				_ => {
-					return Err(RunNodeError::BadParameterType {
+
+		let class = {
+			let id = params.pop_int("class")?;
+			ctx.itemdb_client
+				.get_class(&mut trans, id.into())
+				.await
+				.map_err(|e| match e {
+					GetClassError::NotFound => RunNodeError::BadParameterOther {
 						parameter: "class".into(),
-					})
-				}
-			}
-		} else {
-			return Err(RunNodeError::MissingParameter {
-				parameter: "class".into(),
-			});
+						message: "this class doesn't exist".into(),
+					},
+					_ => RunNodeError::Other(Arc::new(e)),
+				})?
 		};
 
-		// This is only used by UI, but make sure it's sane.
+		// The `dataset` parameter is only used by UI, but make sure it's sane.
+		{
+			let id = params.pop_int("dataset")?;
 
-		if let Some(value) = params.remove("dataset") {
-			match value {
-				NodeParameterValue::Integer(x) => {
-					let dataset =
-						ctx.itemdb_client
-							.get_dataset(x.into())
-							.await
-							.map_err(|e| match e {
-								GetDatasetError::NotFound => RunNodeError::BadParameterOther {
-									parameter: "dataset".into(),
-									message: "this dataset doesn't exist".into(),
-								},
-								_ => RunNodeError::Other(Arc::new(e)),
-							})?;
-
-					if class.dataset != dataset.id {
-						return Err(RunNodeError::BadParameterOther {
-							parameter: "dataset".into(),
-							message: "this class doesn't belong to this dataset".into(),
-						});
-					}
+			let dataset = ctx
+				.itemdb_client
+				.get_dataset(&mut trans, id.into())
+				.await
+				.map_err(|e| match e {
+					GetDatasetError::NotFound => RunNodeError::BadParameterOther {
+						parameter: "dataset".into(),
+						message: "this dataset doesn't exist".into(),
+					},
+					_ => RunNodeError::Other(Arc::new(e)),
+				})?;
+
+			if class.dataset != dataset.id {
+				return Err(RunNodeError::BadParameterOther {
+					parameter: "dataset".into(),
+					message: "this class doesn't belong to this dataset".into(),
+				});
+			}
 
-					if ctx.run_by_user != dataset.owner {
-						return Err(RunNodeError::NotAuthorized {
-							message: "you do not have permission to modify this dataset".into(),
-						});
-					}
-				}
+			if ctx.run_by_user != dataset.owner {
+				return Err(RunNodeError::NotAuthorized {
+					message: "you do not have permission to modify this dataset".into(),
+				});
+			};
+		};
 
-				_ => {
-					return Err(RunNodeError::BadParameterType {
-						parameter: "dataset".into(),
-					})
-				}
+		let on_unique_violation = match params.pop_str("on_unique_violation")?.as_str() {
+			"fail" => OnUniqueViolation::Fail,
+			"select" => OnUniqueViolation::Select,
+
+			x => {
+				return Err(RunNodeError::BadParameterOther {
+					parameter: "on_unique_violation".into(),
+					message: format!("Invalid value `{x}`, expected one of [`fail`, `select`]"),
+				})
 			}
-		} else {
-			return Err(RunNodeError::MissingParameter {
-				parameter: "dataset".into(),
-			});
 		};
-		if let Some((param, _)) = params.first_key_value() {
-			return Err(RunNodeError::UnexpectedParameter {
-				parameter: param.clone(),
-			});
-		}
+
+		params.err_if_not_empty()?;
 
 		//
 		// Set up attribute table
@@ -116,12 +118,11 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 		//
 
 		debug!(message = "Getting attributes");
-		let mut attributes: BTreeMap<PortName, (AttributeInfo, Option<ResultOrDirect<AttrData>>)> =
-			class
-				.attributes
-				.into_iter()
-				.map(|x| (PortName::new(x.name.as_str()), (x, None)))
-				.collect();
+		let mut attributes: BTreeMap<PortName, (AttributeInfo, Option<AttrData>)> = class
+			.attributes
+			.into_iter()
+			.map(|x| (PortName::new(x.name.as_str()), (x, None)))
+			.collect();
 
 		// Fill attribute table
 		while let Some((port, data)) = input.pop_first() {
@@ -141,8 +142,7 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 						.collect();
 
 					let mut part_counter = 1;
-
-					let mut reader = BytesSourceReader::open(ctx, source).await?;
+					let mut reader = source.build(ctx).await?;
 
 					let mut upload = ctx
 						.objectstore_client
@@ -154,7 +154,7 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 						.await
 						.map_err(|e| RunNodeError::Other(Arc::new(e)))?;
 
-					while let Some(data) = reader.next_fragment(ctx.blob_fragment_size).await? {
+					while let Some(data) = reader.next_fragment().await? {
 						upload
 							.upload_part(&data, part_counter)
 							.await
@@ -169,29 +169,10 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 
 					let attr = attributes.get_mut(&port).unwrap();
 
-					attr.1 = Some(
-						AttrData::Blob {
-							bucket: ctx.objectstore_blob_bucket.clone(),
-							key: new_obj_key,
-						}
-						.into(),
-					)
-				}
-
-				Some(PipeData::TransactionActionResult {
-					action_idx,
-					result_type,
-				}) => {
-					let attr = attributes.get_mut(&port).unwrap();
-
-					if result_type != attr.0.data_type {
-						return Err(RunNodeError::BadInputType { port });
-					}
-
-					attr.1 = Some(ResultOrDirect::Result {
-						action_idx,
-						expected_type: result_type,
-					});
+					attr.1 = Some(AttrData::Blob {
+						bucket: ctx.objectstore_blob_bucket.clone(),
+						key: new_obj_key,
+					})
 				}
 
 				Some(x) => {
@@ -205,7 +186,7 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 						return Err(RunNodeError::BadInputType { port });
 					}
 
-					attr.1 = Some(as_attr.into());
+					attr.1 = Some(as_attr);
 				}
 
 				None => {}
@@ -216,35 +197,60 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 		// Set up and send transaction
 		//
 
-		let action = TransactionAction::AddItem {
-			to_class: class.id,
-			attributes: attributes
-				.into_iter()
-				.map(|(_, (k, d))| (k.id, d))
-				.filter_map(|(k, v)| v.map(|v| (k, v)))
-				.collect(),
+		// Savepoint, in case we need to rollback `add_item`.
+		// See comments below.
+		let mut trans2 = trans.begin().await?;
+
+		let new_item = ctx
+			.itemdb_client
+			.add_item(
+				&mut trans2,
+				class.id,
+				attributes
+					.into_iter()
+					.map(|(_, (k, d))| (k.id, d))
+					.filter_map(|(k, v)| v.map(|v| (k, v)))
+					.collect(),
+			)
+			.await;
+
+		let new_item = match new_item {
+			Ok(x) => {
+				// We added the item successfully,
+				// commit savepoint.
+				trans2.commit().await?;
+				x
+			}
+			Err(err) => match on_unique_violation {
+				OnUniqueViolation::Fail => return Err(RunNodeError::Other(Arc::new(err))),
+				OnUniqueViolation::Select => match err {
+					AddItemError::UniqueViolated {
+						ref conflicting_ids,
+					} => {
+						if conflicting_ids.len() == 1 {
+							// We're not failing the pipeline, so `trans` will be committed.
+							// however, we shouldn't add a new item---so we need to roll back
+							// trans2.
+							trans2.rollback().await?;
+							*conflicting_ids.first().unwrap()
+						} else {
+							return Err(RunNodeError::Other(Arc::new(err)));
+						}
+					}
+					_ => return Err(RunNodeError::Other(Arc::new(err))),
+				},
+			},
 		};
 
-		let mut trans = ctx.transaction.lock().await;
-		let result_type = action.result_type().unwrap();
-		debug!(
-			message = "Registering action",
-			?action,
-			action_idx = trans.len()
+		let mut output = BTreeMap::new();
+		output.insert(
+			PortName::new("new_item"),
+			PipeData::Reference {
+				class: class.id,
+				item: new_item,
+			},
 		);
-		let action_idx = trans.add_action(action);
-
-		output
-			.send(NodeOutput {
-				node: this_node,
-				port: PortName::new("new_item"),
-				data: Some(PipeData::TransactionActionResult {
-					action_idx,
-					result_type,
-				}),
-			})
-			.await?;
-
-		return Ok(());
+
+		return Ok(output);
 	}
 }
diff --git a/copperd/nodes/basic/src/constant.rs b/copperd/nodes/basic/src/constant.rs
index defcc193..c5099d2d 100644
--- a/copperd/nodes/basic/src/constant.rs
+++ b/copperd/nodes/basic/src/constant.rs
@@ -1,32 +1,36 @@
 use async_trait::async_trait;
-use copper_itemdb::client::base::client::ItemdbClient;
 use copper_piper::{
-	base::{Node, NodeOutput, NodeParameterValue, PortName, RunNodeError, ThisNodeInfo},
+	base::{Node, NodeBuilder, NodeParameterValue, PortName, RunNodeError, ThisNodeInfo},
 	data::PipeData,
-	CopperContext, JobRunResult,
+	helpers::NodeParameters,
+	CopperContext,
 };
-use smartstring::{LazyCompact, SmartString};
 use std::collections::BTreeMap;
-use tokio::sync::mpsc;
 
 pub struct Constant {}
 
+impl NodeBuilder for Constant {
+	fn build<'ctx>(&self) -> Box<dyn Node<'ctx>> {
+		Box::new(Self {})
+	}
+}
+
 #[async_trait]
-impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> for Constant {
+impl<'ctx> Node<'ctx> for Constant {
 	async fn run(
 		&self,
-		_ctx: &CopperContext<Itemdb>,
-		this_node: ThisNodeInfo,
-		mut params: BTreeMap<SmartString<LazyCompact>, NodeParameterValue>,
+		_ctx: &CopperContext<'ctx>,
+		_this_node: ThisNodeInfo,
+		mut params: NodeParameters,
 		mut input: BTreeMap<PortName, Option<PipeData>>,
-		output: mpsc::Sender<NodeOutput<PipeData>>,
-	) -> Result<(), RunNodeError<PipeData>> {
+	) -> Result<BTreeMap<PortName, PipeData>, RunNodeError> {
 		//
 		// Extract parameters
 		//
-		let value = if let Some(value) = params.remove("value") {
-			// Convert parameter into pipeline data
-			match value {
+		let value = {
+			let val = params.pop_val("value")?;
+
+			match val {
 				NodeParameterValue::String(value) => PipeData::Text { value },
 				NodeParameterValue::Boolean(value) => PipeData::Boolean { value },
 				NodeParameterValue::Integer(value) => PipeData::Integer {
@@ -39,16 +43,9 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 					})
 				}
 			}
-		} else {
-			return Err(RunNodeError::MissingParameter {
-				parameter: "value".into(),
-			});
 		};
-		if let Some((param, _)) = params.first_key_value() {
-			return Err(RunNodeError::UnexpectedParameter {
-				parameter: param.clone(),
-			});
-		}
+
+		params.err_if_not_empty()?;
 
 		//
 		// Extract input
@@ -60,14 +57,9 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 		//
 		// Return the value we were given
 		//
-		output
-			.send(NodeOutput {
-				node: this_node,
-				port: PortName::new("out"),
-				data: Some(value),
-			})
-			.await?;
 
-		return Ok(());
+		let mut output = BTreeMap::new();
+		output.insert(PortName::new("out"), value);
+		return Ok(output);
 	}
 }
diff --git a/copperd/nodes/basic/src/finditem.rs b/copperd/nodes/basic/src/finditem.rs
deleted file mode 100644
index 14dc14e0..00000000
--- a/copperd/nodes/basic/src/finditem.rs
+++ /dev/null
@@ -1,186 +0,0 @@
-use pipelined_pipeline::{
-    api::{InitNodeError, Node, NodeInfo, NodeState, PipelineData, RunNodeError},
-    dispatcher::NodeParameterValue,
-    labels::PipelinePortID,
-};
-use futures::executor::block_on;
-use smartstring::{LazyCompact, SmartString};
-use std::{collections::BTreeMap, sync::Arc};
-
-use crate::{
-    data::{CopperData, CopperDataStub},
-    CopperContext,
-};
-
-pub struct FindItemInfo {
-    inputs: BTreeMap<PipelinePortID, CopperDataStub>,
-    outputs: BTreeMap<PipelinePortID, CopperDataStub>,
-
-    class: ClassHandle,
-    by_attr: AttrInfo,
-}
-
-impl FindItemInfo {
-    pub fn new(
-        ctx: &CopperContext,
-        params: &BTreeMap<SmartString<LazyCompact>, NodeParameterValue<CopperData>>,
-    ) -> Result<Self, InitNodeError> {
-        if params.len() != 2 {
-            return Err(InitNodeError::BadParameterCount { expected: 2 });
-        }
-
-        let class: ClassHandle = if let Some(value) = params.get("class") {
-            match value {
-                NodeParameterValue::String(s) => {
-                    let x = block_on(ctx.dataset.get_class_by_name(s));
-                    match x {
-                        Ok(Some(x)) => x.handle,
-                        Ok(None) => {
-                            return Err(InitNodeError::BadParameterOther {
-                                param_name: "class".into(),
-                                message: "No such class".into(),
-                            })
-                        }
-                        Err(e) => return Err(InitNodeError::Other(Box::new(e))),
-                    }
-                }
-                _ => {
-                    return Err(InitNodeError::BadParameterType {
-                        param_name: "class".into(),
-                    })
-                }
-            }
-        } else {
-            return Err(InitNodeError::MissingParameter {
-                param_name: "class".into(),
-            });
-        };
-
-        let by_attr: AttrInfo = if let Some(value) = params.get("by_attr") {
-            match value {
-                NodeParameterValue::String(s) => {
-                    let x = block_on(ctx.dataset.get_attr_by_name(class, s));
-                    match x {
-                        Ok(Some(x)) => x.clone(),
-                        Ok(None) => {
-                            return Err(InitNodeError::BadParameterOther {
-                                param_name: "by_attr".into(),
-                                message: "No such attribute".into(),
-                            })
-                        }
-                        Err(e) => return Err(InitNodeError::Other(Box::new(e))),
-                    }
-                }
-                _ => {
-                    return Err(InitNodeError::BadParameterType {
-                        param_name: "by_attr".into(),
-                    })
-                }
-            }
-        } else {
-            return Err(InitNodeError::MissingParameter {
-                param_name: "by_attr".into(),
-            });
-        };
-
-        Ok(Self {
-            inputs: BTreeMap::from([(PipelinePortID::new("attr_value"), by_attr.data_type.into())]),
-            outputs: BTreeMap::from([(
-                PipelinePortID::new("found_item"),
-                CopperDataStub::Reference { class },
-            )]),
-
-            class,
-            by_attr,
-        })
-    }
-}
-
-impl NodeInfo<CopperData> for FindItemInfo {
-    fn inputs(&self) -> &BTreeMap<PipelinePortID, <CopperData as PipelineData>::DataStubType> {
-        &self.inputs
-    }
-
-    fn outputs(&self) -> &BTreeMap<PipelinePortID, <CopperData as PipelineData>::DataStubType> {
-        &self.outputs
-    }
-}
-
-pub struct FindItem {
-    info: FindItemInfo,
-    dataset: Arc<LocalDataset>,
-    attr_value: Option<CopperData>,
-}
-
-impl FindItem {
-    pub fn new(
-        ctx: &CopperContext,
-        params: &BTreeMap<SmartString<LazyCompact>, NodeParameterValue<CopperData>>,
-    ) -> Result<Self, InitNodeError> {
-        if params.len() != 2 {
-            return Err(InitNodeError::BadParameterCount { expected: 2 });
-        }
-
-        let info = FindItemInfo::new(ctx, params)?;
-
-        Ok(Self {
-            info,
-            dataset: ctx.dataset.clone(),
-            attr_value: None,
-        })
-    }
-}
-
-impl Node<CopperData> for FindItem {
-    fn get_info(&self) -> &dyn NodeInfo<CopperData> {
-        &self.info
-    }
-
-    fn take_input(
-        &mut self,
-        target_port: PipelinePortID,
-        input_data: CopperData,
-    ) -> Result<(), RunNodeError> {
-        assert!(target_port == PipelinePortID::new("attr_value"));
-        assert!(input_data.as_stub() == self.info.by_attr.data_type.into());
-        self.attr_value = Some(input_data);
-        return Ok(());
-    }
-
-    fn run(
-        &mut self,
-        send_data: &dyn Fn(PipelinePortID, CopperData) -> Result<(), RunNodeError>,
-    ) -> Result<NodeState, RunNodeError> {
-        if self.attr_value.is_none() {
-            return Ok(NodeState::Pending("waiting for input"));
-        }
-
-        let found = block_on(self.dataset.find_item_with_attr(
-            self.info.by_attr.handle,
-            self.attr_value.as_ref().unwrap().as_db_data().unwrap(),
-        ))
-        .map_err(|e| RunNodeError::Other(Box::new(e)))?;
-
-        // TODO: how to handle multiple found items?
-        if let Some(item) = found.first() {
-            send_data(
-                PipelinePortID::new("found_item"),
-                CopperData::Reference {
-                    class: self.info.class,
-                    item: *item,
-                },
-            )?;
-        } else {
-            send_data(
-                PipelinePortID::new("found_item"),
-                CopperData::None {
-                    data_type: CopperDataStub::Reference {
-                        class: self.info.class,
-                    },
-                },
-            )?;
-        }
-
-        return Ok(NodeState::Done);
-    }
-}
diff --git a/copperd/nodes/basic/src/hash.rs b/copperd/nodes/basic/src/hash.rs
index 95107c57..e17cc579 100644
--- a/copperd/nodes/basic/src/hash.rs
+++ b/copperd/nodes/basic/src/hash.rs
@@ -1,19 +1,16 @@
 use async_trait::async_trait;
-use copper_itemdb::client::base::client::ItemdbClient;
 use copper_piper::{
-	base::{Node, NodeOutput, NodeParameterValue, PortName, RunNodeError, ThisNodeInfo},
+	base::{Node, NodeBuilder, PortName, RunNodeError, ThisNodeInfo},
 	data::PipeData,
-	helpers::BytesSourceReader,
-	CopperContext, JobRunResult,
+	helpers::NodeParameters,
+	CopperContext,
 };
 use copper_util::HashType;
 use sha2::{Digest, Sha256, Sha512};
-use smartstring::{LazyCompact, SmartString};
 use std::{
 	collections::BTreeMap,
 	io::{Cursor, Read},
 };
-use tokio::sync::mpsc;
 use tracing::{debug, trace};
 
 enum HashComputer {
@@ -78,43 +75,43 @@ impl HashComputer {
 
 pub struct Hash {}
 
+impl NodeBuilder for Hash {
+	fn build<'ctx>(&self) -> Box<dyn Node<'ctx>> {
+		Box::new(Self {})
+	}
+}
+
 // Inputs: "data", Bytes
 // Outputs: "hash", Hash
 #[async_trait]
-impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> for Hash {
+impl<'ctx> Node<'ctx> for Hash {
 	async fn run(
 		&self,
-		ctx: &CopperContext<Itemdb>,
+		ctx: &CopperContext<'ctx>,
 		this_node: ThisNodeInfo,
-		mut params: BTreeMap<SmartString<LazyCompact>, NodeParameterValue>,
+		mut params: NodeParameters,
 		mut input: BTreeMap<PortName, Option<PipeData>>,
-		output: mpsc::Sender<NodeOutput<PipeData>>,
-	) -> Result<(), RunNodeError<PipeData>> {
+	) -> Result<BTreeMap<PortName, PipeData>, RunNodeError> {
 		//
 		// Extract parameters
 		//
-		let hash_type: HashType = if let Some(value) = params.remove("hash_type") {
-			match value {
-				NodeParameterValue::String(hash_type) => {
-					// TODO: this is a hack
-					serde_json::from_str(&format!("\"{hash_type}\"")).unwrap()
-				}
-				_ => {
-					return Err(RunNodeError::BadParameterType {
+		let hash_type: HashType = {
+			let s = params.pop_str("hash_type")?;
+			match s.as_str() {
+				"MD5" => HashType::MD5,
+				"SHA256" => HashType::SHA256,
+				"SHA512" => HashType::SHA512,
+
+				x => {
+					return Err(RunNodeError::BadParameterOther {
 						parameter: "hash_type".into(),
+						message: format!("Invalid hash type `{x}`"),
 					})
 				}
 			}
-		} else {
-			return Err(RunNodeError::MissingParameter {
-				parameter: "hash_type".into(),
-			});
 		};
-		if let Some((param, _)) = params.first_key_value() {
-			return Err(RunNodeError::UnexpectedParameter {
-				parameter: param.clone(),
-			});
-		}
+
+		params.err_if_not_empty()?;
 
 		//
 		// Extract inputs
@@ -141,7 +138,7 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 				})
 			}
 
-			Some(PipeData::Blob { source, .. }) => BytesSourceReader::open(ctx, source).await?,
+			Some(PipeData::Blob { source, .. }) => source.build(ctx).await?,
 
 			_ => {
 				return Err(RunNodeError::BadInputType {
@@ -159,7 +156,7 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 		);
 		let mut hasher = HashComputer::new(hash_type);
 
-		while let Some(data) = reader.next_fragment(ctx.blob_fragment_size).await? {
+		while let Some(data) = reader.next_fragment().await? {
 			hasher = tokio::task::spawn_blocking(move || {
 				let res = hasher.update(&mut Cursor::new(&*data));
 				if let Err(e) = res {
@@ -175,14 +172,9 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 			message = "Hash ready, sending output",
 			node_id = ?this_node.id
 		);
-		output
-			.send(NodeOutput {
-				node: this_node,
-				port: PortName::new("hash"),
-				data: Some(hasher.finish()),
-			})
-			.await?;
 
-		return Ok(());
+		let mut output = BTreeMap::new();
+		output.insert(PortName::new("hash"), hasher.finish());
+		return Ok(output);
 	}
 }
diff --git a/copperd/nodes/basic/src/ifnone.rs b/copperd/nodes/basic/src/ifnone.rs
index 8721740c..20376302 100644
--- a/copperd/nodes/basic/src/ifnone.rs
+++ b/copperd/nodes/basic/src/ifnone.rs
@@ -1,39 +1,38 @@
 use async_trait::async_trait;
-use copper_itemdb::client::base::client::ItemdbClient;
 use copper_piper::{
-	base::{Node, NodeOutput, NodeParameterValue, PortName, RunNodeError, ThisNodeInfo},
+	base::{Node, NodeBuilder, PortName, RunNodeError, ThisNodeInfo},
 	data::PipeData,
-	CopperContext, JobRunResult,
+	helpers::NodeParameters,
+	CopperContext,
 };
-use smartstring::{LazyCompact, SmartString};
 use std::collections::BTreeMap;
-use tokio::sync::mpsc;
 
 pub struct IfNone {}
 
+impl NodeBuilder for IfNone {
+	fn build<'ctx>(&self) -> Box<dyn Node<'ctx>> {
+		Box::new(Self {})
+	}
+}
+
 // Inputs:
 // - "data", <T>
 // - "ifnone", <T>
 // Outputs:
 // - "out", <T>
 #[async_trait]
-impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> for IfNone {
+impl<'ctx> Node<'ctx> for IfNone {
 	async fn run(
 		&self,
-		_ctx: &CopperContext<Itemdb>,
-		this_node: ThisNodeInfo,
-		params: BTreeMap<SmartString<LazyCompact>, NodeParameterValue>,
+		_ctx: &CopperContext<'ctx>,
+		_this_node: ThisNodeInfo,
+		params: NodeParameters,
 		mut input: BTreeMap<PortName, Option<PipeData>>,
-		output: mpsc::Sender<NodeOutput<PipeData>>,
-	) -> Result<(), RunNodeError<PipeData>> {
+	) -> Result<BTreeMap<PortName, PipeData>, RunNodeError> {
 		//
 		// Extract parameters
 		//
-		if let Some((param, _)) = params.first_key_value() {
-			return Err(RunNodeError::UnexpectedParameter {
-				parameter: param.clone(),
-			});
-		}
+		params.err_if_not_empty()?;
 
 		//
 		// Extract input
@@ -71,24 +70,14 @@ impl<Itemdb: ItemdbClient> Node<JobRunResult, PipeData, CopperContext<Itemdb>> f
 			return Err(RunNodeError::UnrecognizedInput { port });
 		}
 
+		let mut output = BTreeMap::new();
+
 		if let Some(data) = data {
-			output
-				.send(NodeOutput {
-					node: this_node,
-					port: PortName::new("out"),
-					data: Some(data),
-				})
-				.await?;
-			return Ok(());
+			output.insert(PortName::new("out"), data);
+		} else if let Some(ifnone) = ifnone {
+			output.insert(PortName::new("out"), ifnone);
 		};
 
-		output
-			.send(NodeOutput {
-				node: this_node,
-				port: PortName::new("out"),
-				data: ifnone,
-			})
-			.await?;
-		return Ok(());
+		return Ok(output);
 	}
 }
diff --git a/copperd/nodes/basic/src/lib.rs b/copperd/nodes/basic/src/lib.rs
index 107c5e11..3156ff6d 100644
--- a/copperd/nodes/basic/src/lib.rs
+++ b/copperd/nodes/basic/src/lib.rs
@@ -1,11 +1,6 @@
 use std::collections::BTreeMap;
 
-use copper_itemdb::client::base::client::ItemdbClient;
-use copper_piper::{
-	base::{NodeDispatcher, RegisterNodeError},
-	data::PipeData,
-	CopperContext, JobRunResult,
-};
+use copper_piper::base::{NodeDispatcher, RegisterNodeError};
 
 mod additem;
 mod constant;
@@ -13,26 +8,11 @@ mod hash;
 mod ifnone;
 
 /// Register all nodes in this module into the given runner.
-pub fn register<Itemdb: ItemdbClient>(
-	dispatcher: &mut NodeDispatcher<JobRunResult, PipeData, CopperContext<Itemdb>>,
-) -> Result<(), RegisterNodeError> {
-	dispatcher.register_node("IfNone", BTreeMap::new(), &|| Box::new(ifnone::IfNone {}))?;
-	dispatcher.register_node("Hash", BTreeMap::new(), &|| Box::new(hash::Hash {}))?;
-	dispatcher.register_node("Constant", BTreeMap::new(), &|| {
-		Box::new(constant::Constant {})
-	})?;
-
-	dispatcher.register_node("AddItem", BTreeMap::new(), &|| {
-		Box::new(additem::AddItem {})
-	})?;
-
-	/*
-	dispatcher.register_node(
-		"FindItem",
-		BTreeMap::new(),
-		&|ctx, params, _| Ok(Box::new(finditem::FindItem::new(ctx, params)?)),
-	)?;
-	*/
+pub fn register(dispatcher: &mut NodeDispatcher) -> Result<(), RegisterNodeError> {
+	dispatcher.register_node("IfNone", BTreeMap::new(), Box::new(ifnone::IfNone {}))?;
+	dispatcher.register_node("Hash", BTreeMap::new(), Box::new(hash::Hash {}))?;
+	dispatcher.register_node("Constant", BTreeMap::new(), Box::new(constant::Constant {}))?;
+	dispatcher.register_node("AddItem", BTreeMap::new(), Box::new(additem::AddItem {}))?;
 
 	return Ok(());
 }
diff --git a/pipelines/addtext.json b/pipelines/addtext.json
deleted file mode 100644
index 36c0111b..00000000
--- a/pipelines/addtext.json
+++ /dev/null
@@ -1,35 +0,0 @@
-{
-	"job_id": "text",
-	"input": { "testdata": { "type": "Text", "value": "this is test data" } },
-	"pipeline": {
-		"edges": {
-			"e": {
-				"source": {
-					"node": "input",
-					"port": "out"
-				},
-				"target": {
-					"node": "b",
-					"port": "title"
-				}
-			}
-		},
-		"nodes": {
-			"input": {
-				"node_type": "Input",
-				"params": {
-					"input_name": {
-						"parameter_type": "String",
-						"value": "testdata"
-					}
-				}
-			},
-			"b": {
-				"node_type": "AddItem",
-				"params": {
-					"class": { "parameter_type": "Integer", "value": 2 }
-				}
-			}
-		}
-	}
-}
diff --git a/pipelines/audiofile.json b/pipelines/audiofile.json
deleted file mode 100644
index bc528294..00000000
--- a/pipelines/audiofile.json
+++ /dev/null
@@ -1,275 +0,0 @@
-{
-	"job_id": "audiofile",
-	"input": {
-		"file_data": {
-			"type": "Blob",
-			"object_key": "Avril Lavigne - Complicated.flac"
-		}
-	},
-	"pipeline": {
-		"edges": {
-			"in-strip": {
-				"source": {
-					"node": "input",
-					"port": "out"
-				},
-				"target": {
-					"node": "strip",
-					"port": "data"
-				}
-			},
-			"in-tags": {
-				"source": {
-					"node": "input",
-					"port": "out"
-				},
-				"target": {
-					"node": "tags",
-					"port": "data"
-				}
-			},
-			"in-cover": {
-				"source": {
-					"node": "input",
-					"port": "out"
-				},
-				"target": {
-					"node": "cover",
-					"port": "data"
-				}
-			},
-			"strip-hash": {
-				"source": {
-					"node": "strip",
-					"port": "out"
-				},
-				"target": {
-					"node": "hash",
-					"port": "data"
-				}
-			},
-			"strip-add": {
-				"source": {
-					"node": "strip",
-					"port": "out"
-				},
-				"target": {
-					"node": "addaudio",
-					"port": "audio_data"
-				}
-			},
-			"hash-add": {
-				"source": {
-					"node": "hash",
-					"port": "hash"
-				},
-				"target": {
-					"node": "addaudio",
-					"port": "audio_hash"
-				}
-			},
-			"cover-coverhash": {
-				"source": {
-					"node": "cover",
-					"port": "cover_data"
-				},
-				"target": {
-					"node": "coverhash",
-					"port": "data"
-				}
-			},
-			"coverhash-add": {
-				"source": {
-					"node": "coverhash",
-					"port": "hash"
-				},
-				"target": {
-					"node": "addcover",
-					"port": "content_hash"
-				}
-			},
-			"cover-add": {
-				"source": {
-					"node": "cover",
-					"port": "cover_data"
-				},
-				"target": {
-					"node": "addcover",
-					"port": "image"
-				}
-			},
-			"link-cover": {
-				"source": {
-					"node": "addcover",
-					"port": "new_item"
-				},
-				"target": {
-					"node": "addaudio",
-					"port": "cover_art"
-				}
-			},
-			"tag-title": {
-				"source": {
-					"node": "tags",
-					"port": "Title"
-				},
-				"target": {
-					"node": "addaudio",
-					"port": "title"
-				}
-			},
-			"tag-album": {
-				"source": {
-					"node": "tags",
-					"port": "Album"
-				},
-				"target": {
-					"node": "addaudio",
-					"port": "album"
-				}
-			},
-			"tag-artist": {
-				"source": {
-					"node": "tags",
-					"port": "Artist"
-				},
-				"target": {
-					"node": "addaudio",
-					"port": "artist"
-				}
-			},
-			"tag-albumartist": {
-				"source": {
-					"node": "tags",
-					"port": "AlbumArtist"
-				},
-				"target": {
-					"node": "addaudio",
-					"port": "albumartist"
-				}
-			},
-			"tag-tracknumber": {
-				"source": {
-					"node": "tags",
-					"port": "TrackNumber"
-				},
-				"target": {
-					"node": "addaudio",
-					"port": "tracknumber"
-				}
-			},
-			"tag-year": {
-				"source": {
-					"node": "tags",
-					"port": "Year"
-				},
-				"target": {
-					"node": "addaudio",
-					"port": "year"
-				}
-			},
-			"tag-genre": {
-				"source": {
-					"node": "tags",
-					"port": "Genre"
-				},
-				"target": {
-					"node": "addaudio",
-					"port": "genre"
-				}
-			},
-			"tag-isrc": {
-				"source": {
-					"node": "tags",
-					"port": "ISRC"
-				},
-				"target": {
-					"node": "addaudio",
-					"port": "ISRC"
-				}
-			},
-			"tag-lyrics": {
-				"source": {
-					"node": "tags",
-					"port": "Lyrics"
-				},
-				"target": {
-					"node": "addaudio",
-					"port": "lyrics"
-				}
-			}
-		},
-		"nodes": {
-			"input": {
-				"node_type": "Input",
-				"params": {
-					"input_name": {
-						"parameter_type": "String",
-						"value": "file_data"
-					}
-				}
-			},
-			"strip": {
-				"node_type": "StripTags"
-			},
-			"cover": {
-				"node_type": "ExtractCovers"
-			},
-			"tags": {
-				"node_type": "ExtractTags",
-				"params": {
-					"tags": {
-						"parameter_type": "List",
-						"value": [
-							{ "parameter_type": "String", "value": "Title" },
-							{ "parameter_type": "String", "value": "Album" },
-							{ "parameter_type": "String", "value": "Artist" },
-							{ "parameter_type": "String", "value": "Year" },
-							{ "parameter_type": "String", "value": "Genre" },
-							{ "parameter_type": "String", "value": "ISRC" },
-							{ "parameter_type": "String", "value": "Lyrics" },
-							{
-								"parameter_type": "String",
-								"value": "AlbumArtist"
-							},
-							{
-								"parameter_type": "String",
-								"value": "TrackNumber"
-							}
-						]
-					}
-				}
-			},
-			"hash": {
-				"node_type": "Hash",
-				"params": {
-					"hash_type": {
-						"parameter_type": "String",
-						"value": "SHA256"
-					}
-				}
-			},
-			"coverhash": {
-				"node_type": "Hash",
-				"params": {
-					"hash_type": {
-						"parameter_type": "String",
-						"value": "SHA256"
-					}
-				}
-			},
-			"addaudio": {
-				"node_type": "AddItem",
-				"params": {
-					"class": { "parameter_type": "Integer", "value": 2 }
-				}
-			},
-			"addcover": {
-				"node_type": "AddItem",
-				"params": {
-					"class": { "parameter_type": "Integer", "value": 1 }
-				}
-			}
-		}
-	}
-}
diff --git a/pipelines/empty.json b/pipelines/empty.json
deleted file mode 100644
index aa54bb37..00000000
--- a/pipelines/empty.json
+++ /dev/null
@@ -1,8 +0,0 @@
-{
-	"job_id": "empty",
-	"input": {},
-	"pipeline": {
-		"edges": {},
-		"nodes": {}
-	}
-}