build(editor): Add the frontend module workspace layout and shared tsconfig base (no-changelog) (#35957)

Co-authored-by: multica-agent <github@multica.ai>

.github/workflows/test-unit-reusable.yml

@@ -66,7 +66,7 @@ jobs:
       # @n8n/vitest-config/node), peak forks ≈ 2 × 50% ≈ the core count, instead
       # of ~10 concurrent suites each spawning a core-sized pool and pegging CPU.
       - name: Test Unit (backend, except cli and nodes-base)
-        run: pnpm turbo test:unit --continue --concurrency=2 --filter='!./packages/frontend/**' --filter='!n8n' --filter='!n8n-nodes-base' --summarize
+        run: pnpm turbo test:unit --continue --concurrency=2 --filter='!./packages/frontend/**' --filter='!./packages/modules/**' --filter='!n8n' --filter='!n8n-nodes-base' --summarize
 
       - name: Test Unit (cli, scoped)
         if: ${{ !cancelled() }}
@@ -126,7 +126,7 @@ jobs:
       # run serially to avoid cross-package interference. Unit jobs above
       # don't need this because they isolate per-process.
       - name: Test Integration (backend, except cli)
-        run: pnpm turbo test:integration --continue --concurrency=1 --filter='!./packages/frontend/**' --filter='!n8n' --summarize
+        run: pnpm turbo test:integration --continue --concurrency=1 --filter='!./packages/frontend/**' --filter='!./packages/modules/**' --filter='!n8n' --summarize
 
       - name: Test Integration (cli, scoped)
         if: ${{ !cancelled() }}

biome.jsonc

@@ -42,6 +42,14 @@
 		]
 	},
 	"organizeImports": { "enabled": false },
+	// Every `tsconfig*.json` is JSONC. Biome only infers that from the exact name `tsconfig.json`,
+	// so variants like `tsconfig.frontend-module.json` need it spelled out.
+	"overrides": [
+		{
+			"include": ["**/tsconfig*.json"],
+			"json": { "parser": { "allowComments": true } }
+		}
+	],
 	"linter": {
 		"enabled": false
 	},

package.json

@@ -58,12 +58,12 @@
     "mutate": "node scripts/mutation-health/mutate.mjs",
     "test": "turbo run test",
     "test:ci": "turbo run test --continue --concurrency=1",
-    "test:ci:frontend": "turbo run test --continue --filter='./packages/frontend/**'",
-    "test:ci:frontend:changed": "turbo run test:changed --continue --filter='./packages/frontend/**'",
-    "test:ci:backend": "turbo run test --continue --concurrency=1 --filter='!./packages/frontend/**'",
-    "test:ci:backend:unit": "turbo run test:unit --continue --filter='!./packages/frontend/**'",
-    "test:ci:backend:integration": "turbo run test:integration --continue --concurrency=1 --filter='!./packages/frontend/**'",
-    "test:ci:backend:integration:changed": "turbo run test:integration:changed --continue --concurrency=1 --filter='!./packages/frontend/**'",
+    "test:ci:frontend": "turbo run test --continue --filter='./packages/frontend/**' --filter='./packages/modules/**'",
+    "test:ci:frontend:changed": "turbo run test:changed --continue --filter='./packages/frontend/**' --filter='./packages/modules/**'",
+    "test:ci:backend": "turbo run test --continue --concurrency=1 --filter='!./packages/frontend/**' --filter='!./packages/modules/**'",
+    "test:ci:backend:unit": "turbo run test:unit --continue --filter='!./packages/frontend/**' --filter='!./packages/modules/**'",
+    "test:ci:backend:integration": "turbo run test:integration --continue --concurrency=1 --filter='!./packages/frontend/**' --filter='!./packages/modules/**'",
+    "test:ci:backend:integration:changed": "turbo run test:integration:changed --continue --concurrency=1 --filter='!./packages/frontend/**' --filter='!./packages/modules/**'",
     "test:affected": "turbo run test --affected --concurrency=1",
     "db:schema:docs": "turbo run build --filter=@n8n/db && pnpm --filter=@n8n/db schema:docs",
     "db:schema:check": "turbo run build --filter=@n8n/db && pnpm --filter=@n8n/db schema:check",

packages/@n8n/typescript-config/package.json

@@ -6,13 +6,15 @@
     "tsconfig.backend.json",
     "tsconfig.build.json",
     "tsconfig.common.json",
-    "tsconfig.frontend.json"
+    "tsconfig.frontend.json",
+    "tsconfig.frontend-module.json"
   ],
   "exports": {
     "./tsconfig.backend.json": "./tsconfig.backend.json",
     "./tsconfig.build.json": "./tsconfig.build.json",
     "./tsconfig.common.json": "./tsconfig.common.json",
     "./tsconfig.frontend.json": "./tsconfig.frontend.json",
+    "./tsconfig.frontend-module.json": "./tsconfig.frontend-module.json",
     "./*": "./*"
   },
   "license": "LicenseRef-n8n-sustainable-use"

packages/@n8n/typescript-config/tsconfig.frontend-module.json

@@ -0,0 +1,53 @@
+// Base tsconfig for frontend module packages (`packages/modules/*/frontend`).
+//
+// Hand-maintained, and it has to agree with editor-ui's Vite aliases and its own tsconfig `paths`
+// — a package pointed at a different src here would typecheck modules against something the
+// editor never bundles. `editor-ui/vite/aliases.test.ts` fails when they disagree.
+//
+// `paths` lists the L0-L2 packages a module consumes from source. Module packages are absent
+// from it on purpose, which stops an *accidental* cross-module import — but it is not a
+// boundary: `paths` is additive, so once a module declares another module as a dependency,
+// pnpm symlinks it and the import typechecks clean. Boundary enforcement is the ESLint rule.
+//
+// Modules declare their own `include`, `rootDirs` and `types`, and cannot inherit them: relative
+// entries in those three resolve against the *consuming* config, so inheriting them from here
+// would point them at this directory. `paths` is the exception — it anchors to the file that
+// declares it, which is what lets one base serve modules at any depth.
+//
+// `useUnknownInCatchVariables` is a cost of consuming L1/L2 packages from source rather than from
+// a built `dist`; see the comment on it below. The ambient `.d.ts` shims are the other half of
+// that cost, and live in each module's own tsconfig for the resolution reason above.
+{
+	"extends": "./tsconfig.frontend.json",
+	"compilerOptions": {
+		"moduleResolution": "bundler",
+		"noEmit": true,
+		"useUnknownInCatchVariables": false,
+		"paths": {
+			"@n8n/api-types": ["../api-types/src/index.ts"],
+			"@n8n/api-types/*": ["../api-types/src/*"],
+			"@n8n/chat": ["../../frontend/@n8n/chat/src/index.ts"],
+			"@n8n/chat/*": ["../../frontend/@n8n/chat/src/*"],
+			"@n8n/chat-hub": ["../chat-hub/src/index.ts"],
+			"@n8n/chat-hub/*": ["../chat-hub/src/*"],
+			"@n8n/composables/*": ["../../frontend/@n8n/composables/src/*"],
+			"@n8n/constants": ["../constants/src/index.ts"],
+			"@n8n/constants/*": ["../constants/src/*"],
+			"@n8n/design-system": ["../../frontend/@n8n/design-system/src/index.ts"],
+			"@n8n/design-system/*": ["../../frontend/@n8n/design-system/src/*"],
+			"@n8n/frontend-constants/*": ["../../frontend/@n8n/frontend-constants/src/*"],
+			"@n8n/frontend-module-sdk": ["../../frontend/@n8n/frontend-module-sdk/src/index.ts"],
+			"@n8n/frontend-module-sdk/*": ["../../frontend/@n8n/frontend-module-sdk/src/*"],
+			"@n8n/frontend-utils/*": ["../../frontend/@n8n/frontend-utils/src/*"],
+			"@n8n/i18n": ["../../frontend/@n8n/i18n/src/index.ts"],
+			"@n8n/i18n/*": ["../../frontend/@n8n/i18n/src/*"],
+			"@n8n/rest-api-client": ["../../frontend/@n8n/rest-api-client/src/index.ts"],
+			"@n8n/rest-api-client/*": ["../../frontend/@n8n/rest-api-client/src/*"],
+			"@n8n/stores": ["../../frontend/@n8n/stores/src/index.ts"],
+			"@n8n/stores/*": ["../../frontend/@n8n/stores/src/*"],
+			"@n8n/telemetry": ["../telemetry/src/index.ts"],
+			"@n8n/telemetry/*": ["../telemetry/src/*"],
+			"@n8n/utils/*": ["../utils/src/*"]
+		}
+	}
+}

packages/modules/README.md

@@ -0,0 +1,13 @@
+# Modules
+
+Feature modules carved out of `packages/frontend/editor-ui`. Each one is a workspace package at
+`<name>/frontend`: source-only (`main: "src/index.ts"`, no `dist`), consumed by the editor-ui shell
+through Vite aliases.
+
+`<name>/backend` is a reserved path rather than a workspace package — the backend runtime discovers
+modules under `packages/cli/src/modules/<name>`. The extra nesting level is what lets both halves of
+a module sit together later.
+
+The directory is empty until the first module lands, and tracked in the meantime because turbo
+rejects a `--filter` whose directory does not exist. The root `test:ci:*` scripts and the two
+backend jobs in `.github/workflows/test-unit-reusable.yml` all name `packages/modules/**`.

pnpm-workspace.yaml

@@ -2,6 +2,9 @@ packages:
   - packages/*
   - packages/@n8n/*
   - packages/frontend/**
+  # `packages/*` stops one level short of `<module>/frontend`, so feature modules need their own
+  # glob or they are not workspace packages at all.
+  - packages/modules/**
   - packages/extensions/**
   - packages/testing/**