diff --git a/README.md b/README.md
index 62d72d7dee..a8d57d9ed3 100644
--- a/README.md
+++ b/README.md
@@ -191,8 +191,10 @@ let author = "Example <example@example.com>"
 let info fmt = Irmin_git_unix.info ~author fmt
 
 let main () =
+  (* Create the switch *)
+  Eio.Switch.run @@ fun sw ->
   (* Open the repo *)
-  let repo = Store.Repo.v config in
+  let repo = Store.Repo.v ~sw config in
 
   (* Load the main branch *)
   let t = Store.main repo in
diff --git a/irmin-server.opam b/irmin-server.opam
index fcf342ddde..1379cd3f96 100644
--- a/irmin-server.opam
+++ b/irmin-server.opam
@@ -21,6 +21,7 @@ depends: [
   "websocket-lwt-unix"
   "cohttp-lwt-unix"
   "ppx_blob"
+  "alcotest-lwt"     {with-test}
 ]
 
 build: [
diff --git a/src/irmin-containers/linked_log.ml b/src/irmin-containers/linked_log.ml
index dcd0d16cc8..cda30decc5 100644
--- a/src/irmin-containers/linked_log.ml
+++ b/src/irmin-containers/linked_log.ml
@@ -43,7 +43,7 @@ struct
 
     let store = ref None
 
-    (* TODO: Fix this hellhole *)
+    (* TODO: Fix me *)
     let get_store () =
       match !store with
       | None ->
diff --git a/src/irmin-pack/unix/async.ml b/src/irmin-pack/unix/async.ml
index 8ac5c5d5b8..c1b2aa28f0 100644
--- a/src/irmin-pack/unix/async.ml
+++ b/src/irmin-pack/unix/async.ml
@@ -45,7 +45,7 @@ module Unix = struct
           Eio.Domain_manager.run (domain_mgr ()) (run f))
     in
     let gc_sw = Eio.Promise.await gc_sw_promise in
-    gc_sw, promise
+    (gc_sw, promise)
 
   let await (_, p) : [> outcome ] =
     match Eio.Promise.await p with
diff --git a/test/irmin-containers/blob_log.ml b/test/irmin-containers/blob_log.ml
index c04d525f3c..c57d39fb35 100644
--- a/test/irmin-containers/blob_log.ml
+++ b/test/irmin-containers/blob_log.ml
@@ -20,19 +20,24 @@ open Common
 module B = Irmin_containers.Blob_log.Mem (Irmin.Contents.String)
 
 let path = [ "tmp"; "blob" ]
-let config ~sw = B.Store.Repo.v ~sw (Irmin_mem.config ())
+
+let config ~sw root =
+  let key = Irmin.Backend.Conf.root Irmin_mem.Conf.spec in
+  let conf = Irmin.Backend.Conf.singleton Irmin_mem.Conf.spec key root in
+  B.Store.Repo.v ~sw conf
+
 let merge_into_exn = merge_into_exn (module B.Store)
 
 let test_empty_read () =
   Eio.Switch.run @@ fun sw ->
-  let config = config ~sw in
+  let config = config ~sw __FUNCTION__ in
   let main = B.Store.main config in
   B.read_all ~path main
   |> Alcotest.(check (list string)) "checked - reading empty log" []
 
 let test_append () =
   Eio.Switch.run @@ fun sw ->
-  let t = config ~sw |> B.Store.main in
+  let t = config ~sw __FUNCTION__ |> B.Store.main in
   B.append ~path t "main.1";
   B.append ~path t "main.2";
   B.read_all ~path t
@@ -41,7 +46,7 @@ let test_append () =
 
 let test_clone_merge () =
   Eio.Switch.run @@ fun sw ->
-  let t = config ~sw |> B.Store.main in
+  let t = config ~sw __FUNCTION__ |> B.Store.main in
   B.append ~path t "main.1";
   B.append ~path t "main.2";
   let b = B.Store.clone ~src:t ~dst:"cl" in
@@ -55,7 +60,7 @@ let test_clone_merge () =
 
 let test_branch_merge () =
   Eio.Switch.run @@ fun sw ->
-  let r = config ~sw in
+  let r = config __FUNCTION__ ~sw in
   let b1 = B.Store.of_branch r "b1" in
   let b2 = B.Store.of_branch r "b2" in
   let b3 = B.Store.of_branch r "b3" in
diff --git a/test/irmin-containers/counter.ml b/test/irmin-containers/counter.ml
index 4cb22002f7..9d3cbcfb01 100644
--- a/test/irmin-containers/counter.ml
+++ b/test/irmin-containers/counter.ml
@@ -20,12 +20,17 @@ open Common
 module C = Irmin_containers.Counter.Mem
 
 let path = [ "tmp"; "counter" ]
-let config ~sw () = C.Store.Repo.v ~sw (Irmin_mem.config ())
+
+let config ~sw root =
+  let key = Irmin.Backend.Conf.root Irmin_mem.Conf.spec in
+  let conf = Irmin.Backend.Conf.singleton Irmin_mem.Conf.spec key root in
+  C.Store.Repo.v ~sw conf
+
 let merge_into_exn = merge_into_exn (module C.Store)
 
 let test_inc () =
   Eio.Switch.run @@ fun sw ->
-  let t = config ~sw () |> C.Store.main in
+  let t = config ~sw __FUNCTION__ |> C.Store.main in
   C.inc ~path t;
   let () =
     C.read ~path t
@@ -36,7 +41,7 @@ let test_inc () =
 
 let test_dec () =
   Eio.Switch.run @@ fun sw ->
-  let t = config ~sw () |> C.Store.main in
+  let t = config ~sw __FUNCTION__ |> C.Store.main in
   C.dec ~path t;
   let () =
     C.read ~path t
@@ -47,7 +52,7 @@ let test_dec () =
 
 let test_clone_merge () =
   Eio.Switch.run @@ fun sw ->
-  let t = config ~sw () |> C.Store.main in
+  let t = config ~sw __FUNCTION__ |> C.Store.main in
   C.inc ~by:5L ~path t;
   let b = C.Store.clone ~src:t ~dst:"cl" in
   C.inc ~by:2L ~path b;
@@ -64,7 +69,7 @@ let test_clone_merge () =
 
 let test_branch_merge () =
   Eio.Switch.run @@ fun sw ->
-  let r = config ~sw () in
+  let r = config ~sw __FUNCTION__ in
   let b1 = C.Store.of_branch r "b1" in
   let b2 = C.Store.of_branch r "b2" in
   let b3 = C.Store.of_branch r "b3" in
diff --git a/test/irmin-containers/linked_log.ml b/test/irmin-containers/linked_log.ml
index 2eaca01c5e..b3fd352f98 100644
--- a/test/irmin-containers/linked_log.ml
+++ b/test/irmin-containers/linked_log.ml
@@ -28,18 +28,22 @@ module L = Irmin_containers.Linked_log.Mem (CAS) (Irmin.Contents.String) ()
 
 let merge_into_exn = merge_into_exn (module L.Store)
 let path = [ "tmp"; "link" ]
-let config ~sw = L.Store.Repo.v ~sw (Irmin_mem.config ())
+
+let config ~sw root =
+  let key = Irmin.Backend.Conf.root Irmin_mem.Conf.spec in
+  let conf = Irmin.Backend.Conf.singleton Irmin_mem.Conf.spec key root in
+  L.Store.Repo.v ~sw conf
 
 let test_empty_read () =
   Eio.Switch.run @@ fun sw ->
-  config ~sw
+  config ~sw __FUNCTION__
   |> L.Store.main
   |> L.read_all ~path
   |> Alcotest.(check (list string)) "checked - reading empty log" []
 
 let test_append_read_all () =
   Eio.Switch.run @@ fun sw ->
-  let t = config ~sw |> L.Store.main in
+  let t = config ~sw __FUNCTION__ |> L.Store.main in
   L.append ~path t "main.1";
   L.append ~path t "main.2";
   L.read_all ~path t
@@ -48,7 +52,7 @@ let test_append_read_all () =
 
 let test_read_incr () =
   Eio.Switch.run @@ fun sw ->
-  let t = config ~sw |> L.Store.main in
+  let t = config ~sw __FUNCTION__ |> L.Store.main in
   L.append ~path t "main.1";
   L.append ~path t "main.2";
   let cur = L.get_cursor ~path t in
@@ -61,7 +65,7 @@ let test_read_incr () =
 
 let test_read_excess () =
   Eio.Switch.run @@ fun sw ->
-  let t = config ~sw |> L.Store.main in
+  let t = config ~sw __FUNCTION__ |> L.Store.main in
   L.append ~path t "main.1";
   L.append ~path t "main.2";
   let cur = L.get_cursor ~path t in
@@ -71,7 +75,7 @@ let test_read_excess () =
 
 let test_clone_merge () =
   Eio.Switch.run @@ fun sw ->
-  let t = config ~sw |> L.Store.main in
+  let t = config ~sw __FUNCTION__ |> L.Store.main in
   L.append ~path t "main.1";
   L.append ~path t "main.2";
   let b = L.Store.clone ~src:t ~dst:"cl" in
@@ -85,7 +89,7 @@ let test_clone_merge () =
 
 let test_branch_merge () =
   Eio.Switch.run @@ fun sw ->
-  let r = config ~sw in
+  let r = config ~sw __FUNCTION__ in
   let b1 = L.Store.of_branch r "b1" in
   let b2 = L.Store.of_branch r "b2" in
   let b3 = L.Store.of_branch r "b3" in
diff --git a/test/irmin-pack/test_corrupted.ml b/test/irmin-pack/test_corrupted.ml
index 8ba049579b..bd5532f4c5 100644
--- a/test/irmin-pack/test_corrupted.ml
+++ b/test/irmin-pack/test_corrupted.ml
@@ -70,7 +70,8 @@ let test_corrupted_control_file () =
   assert (not (String.equal control_file_blob1 control_file_mix));
   write_file control_file_path control_file_mix;
   let error =
-    try Ok (Store.Repo.v ~sw (config ~fresh:false root) : Store.Repo.t) with exn -> Error exn
+    try Ok (Store.Repo.v ~sw (config ~fresh:false root) : Store.Repo.t)
+    with exn -> Error exn
   in
   match error with
   | Error (Irmin_pack_unix.Errors.Pack_error (`Corrupted_control_file s)) ->
diff --git a/test/irmin-pack/test_multicore.ml b/test/irmin-pack/test_multicore.ml
index fa62e598f8..9a563da01d 100644
--- a/test/irmin-pack/test_multicore.ml
+++ b/test/irmin-pack/test_multicore.ml
@@ -474,15 +474,15 @@ let tests d_mgr =
   [
     tc "find." test_find;
     (* tc "length." test_length;
-    tc "add / remove." test_add_remove;
-    tc "commit." test_commit;
-    tc "merkle." test_merkle;
-    tc "hash." test_hash;
-    tc "list-disk-no-cache." (test_list_disk ~cache:false);
-    tc "list-disk-with-cache." (test_list_disk ~cache:true);
-    tc "list-mem-no-cache." (test_list_mem ~cache:false);
-    tc "list-mem-with-cache." (test_list_mem ~cache:true);
-    tc "commit-of-hash." test_commit_of_hash;
-    tc "commit-parents." test_commit_parents;
-    tc "commit-v." test_commit_v; *)
+       tc "add / remove." test_add_remove;
+       tc "commit." test_commit;
+       tc "merkle." test_merkle;
+       tc "hash." test_hash;
+       tc "list-disk-no-cache." (test_list_disk ~cache:false);
+       tc "list-disk-with-cache." (test_list_disk ~cache:true);
+       tc "list-mem-no-cache." (test_list_mem ~cache:false);
+       tc "list-mem-with-cache." (test_list_mem ~cache:true);
+       tc "commit-of-hash." test_commit_of_hash;
+       tc "commit-parents." test_commit_parents;
+       tc "commit-v." test_commit_v; *)
   ]