diff --git a/.cache/vitest/results.json b/.cache/vitest/results.json
new file mode 100644
index 0000000..a8fca10
--- /dev/null
+++ b/.cache/vitest/results.json
@@ -0,0 +1 @@
+{"version":"2.1.5","results":[["packages/playground:packages/playground/src/demo/index.test.js",{"duration":0,"failed":false}]]}
\ No newline at end of file
diff --git a/package.json b/package.json
index 926896f..97974e0 100644
--- a/package.json
+++ b/package.json
@@ -21,11 +21,15 @@
     "release": "npm run release --workspaces",
     "release:proof": "npx dotenv-cli -- npm run release -- -- --dry-run",
     "test": "vitest",
+    "test:observables": "vitest --project packages/observables",
+    "test:operators": "vitest --project packages/operators",
+    "test:playground": "vitest --project packages/playground",
     "coverage": "vitest run --coverage"
   },
   "workspaces": [
     "packages/operators",
-    "packages/observables"
+    "packages/observables",
+    "packages/playground"
   ],
   "devDependencies": {
     "@commitlint/config-conventional": "19.6.0",
diff --git a/packages/observables/vitest.config.js b/packages/observables/vitest.config.js
index e3fd592..e551e50 100644
--- a/packages/observables/vitest.config.js
+++ b/packages/observables/vitest.config.js
@@ -1,7 +1,10 @@
 import { defineProject } from 'vitest/config';
 
 export default defineProject({
+  cacheDir: '../.cache/vitest-observables',
   test: {
+    cacheDir: '../.cache/vitest',
+    setupFiles: ['../../setup.js'],
     environment: 'happy-dom'
   }
 });
diff --git a/packages/operators/vitest.config.js b/packages/operators/vitest.config.js
index 42a246b..675d747 100644
--- a/packages/operators/vitest.config.js
+++ b/packages/operators/vitest.config.js
@@ -1,7 +1,9 @@
-import { defineProject } from 'vitest/config';
+import { defineProject, configDefaults } from 'vitest/config';
 
 export default defineProject({
+  cacheDir: '../.cache/vitest-operators',
   test: {
+    cacheDir: '../.cache/vitest',
     setupFiles: ['../../setup.js'],
     testTimeout: 10000,
     environment: 'happy-dom'
diff --git a/packages/playground/package.json b/packages/playground/package.json
new file mode 100644
index 0000000..b50a2d1
--- /dev/null
+++ b/packages/playground/package.json
@@ -0,0 +1,34 @@
+{
+  "name": "@rxjs-collection/playground",
+  "version": "1.0.12",
+  "description": "rxjs playground",
+  "license": "MIT",
+  "contributors": [
+    {
+      "name": "Stephan Gerbeth",
+      "email": "stephan.gerbeth@gmail.com"
+    }
+  ],
+  "type": "module",
+  "main": "src/index.js",
+  "files": [
+    "./src/*"
+  ],
+  "scripts": {
+    "release": "npx semantic-release",
+    "dev": "npx vitest"
+  },
+  "imports": {
+    "#observables/*": "../observables/src/*",
+    "#operators/*": "../operators/src/*",
+    "#mocks/*": "../mocks/*"
+  },
+  "dependencies": {
+    "@rxjs-collection/observables": "*",
+    "@rxjs-collection/operators": "*",
+    "rxjs": "7.8.1"
+  },
+  "devDependencies": {
+    "node-fetch": "3.3.2"
+  }
+}
diff --git a/packages/playground/src/demo/index.test.js b/packages/playground/src/demo/index.test.js
new file mode 100644
index 0000000..6d32614
--- /dev/null
+++ b/packages/playground/src/demo/index.test.js
@@ -0,0 +1,14 @@
+import { delay, from } from 'rxjs';
+import { describe, test } from 'vitest';
+
+describe('playground stephan', () => {
+  test('basics', async () => {
+    const s = from([1, 2, 3, 4, 5, 6, 7, 8, 9])
+      .pipe(delay(4000))
+      .subscribe(e => {
+        console.log(e);
+        // s.unsubscribe();
+      });
+    await new Promise(done => setTimeout(done, 5000));
+  });
+});
diff --git a/packages/playground/vitest.config.js b/packages/playground/vitest.config.js
new file mode 100644
index 0000000..20e7167
--- /dev/null
+++ b/packages/playground/vitest.config.js
@@ -0,0 +1,11 @@
+import { defineProject } from 'vitest/config';
+
+export default defineProject({
+  cacheDir: '../.cache/vitest-playground',
+  test: {
+    cacheDir: '../.cache/vitest',
+    setupFiles: ['../../setup.js'],
+    testTimeout: 10000,
+    environment: 'happy-dom'
+  }
+});
diff --git a/vitest.config.js b/vitest.config.js
index 235745c..fba5d6a 100644
--- a/vitest.config.js
+++ b/vitest.config.js
@@ -2,6 +2,8 @@ import { defineConfig, configDefaults } from 'vitest/config';
 
 export default defineConfig({
   test: {
+    cacheDir: './.cache/vitest',
+
     coverage: {
       provider: 'v8',
       reporter: ['text', 'json', 'lcov', 'html'],
@@ -11,10 +13,10 @@ export default defineConfig({
         'commitlint.config.js',
         'eslint.ignores.js',
         'vitest.workspace.js',
-        './packages/observables/src/index.js',
-        './packages/operators/src/index.js'
+        './packages/mocks/',
+        './packages/*/src/index.js'
       ]
     },
-    include: ['**/packages/**/*.test.js']
+    include: ['./packages/**/*.test.js']
   }
 });
diff --git a/vitest.workspace.js b/vitest.workspace.js
index f62b807..cc011cb 100644
--- a/vitest.workspace.js
+++ b/vitest.workspace.js
@@ -1 +1,18 @@
-export default ['packages/**/vitest.config.js'];
+// export default ['packages/**/vitest.config.js'];
+
+import { readFileSync } from 'node:fs';
+import { defineWorkspace } from 'vitest/config';
+
+const pkg = JSON.parse(readFileSync('./package.json', 'utf-8'));
+
+export default defineWorkspace([
+  ...pkg.workspaces
+    .filter(name => !['scripts'].includes(name))
+    .map(name => ({
+      extends: `./${name}/vitest.config.js`,
+      test: {
+        root: `./${name}`,
+        name
+      }
+    }))
+]);