jupyter · jtpio · Apr 10, 2026 · Mar 31, 2026 · Mar 31, 2026 · Mar 31, 2026
diff --git a/.github/actions/build-dist/action.yml b/.github/actions/build-dist/action.yml
@@ -16,29 +16,14 @@ runs:
       run: |
         hatch build
 
-    - name: Build npm distributions
-      shell: bash
-      run: |
-        mkdir pkgs
-        hatch run npm_pack
-        cp packages/*/*.tgz pkgs
-
     - name: Build checksum file
       shell: bash
       run: |
         cd dist
         sha256sum * | tee SHA256SUMS
-        cd ../pkgs
-        sha256sum * | tee SHA256SUMS
 
     - name: Upload distributions
       uses: actions/upload-artifact@v4
       with:
         name: notebook-dist-${{ github.run_number }}
         path: ./dist
-
-    - name: Upload distributions
-      uses: actions/upload-artifact@v4
-      with:
-        name: notebook-pkgs-${{ github.run_number }}
-        path: ./pkgs
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
@@ -192,12 +192,12 @@ jobs:
           hatch run lint:build
           pipx run interrogate -v .
           pipx run doc8 --max-line-length=200 docs/source *.md
-          npm install -g yarn
-          yarn
-          yarn eslint:check
-          yarn prettier:check
-          yarn build:utils
-          yarn integrity
+          python -m pip install -U "jupyterlab>=4.6.0a0,<4.7"
+          jlpm
+          jlpm eslint:check
+          jlpm prettier:check
+          jlpm build:utils
+          jlpm integrity
 
   tests_check: # This job does nothing and is only used for the branch protection
     if: always()

diff --git a/.github/workflows/buildutils.yml b/.github/workflows/buildutils.yml
@@ -38,32 +38,84 @@ jobs:
           git config --global user.email "you@example.com"
           git config --global user.name "Your Name"
 
-      - name: Reset version
+      - name: Check Notebook versioning flow
         run: |
+          set -eux
+
+          assert_release_state() {
+            local py_expected="$1"
+            local js_expected="$2"
+
+            test "$(hatch version)" = "${py_expected}"
+            grep -nF "__version__ = \"${py_expected}\"" notebook/_version.py
+            grep -nF "\"version\": \"${js_expected}\"" \
+              buildutils/package.json \
+              packages/application/package.json \
+              packages/lab-extension/package.json
+            grep -nF "\"@jupyter-notebook/application\": \"^${js_expected}\"" \
+              packages/application-extension/package.json \
+              packages/lab-extension/package.json
+            grep -nF "\"@jupyter-notebook/application\": \"~${js_expected}\"" \
+              app/package.json
+            grep -nF '"version": "0.1.0"' package.json ui-tests/package.json
+          }
+
           hatch version 9.8.7
-          jlpm run lerna version 9.8.7 --no-push --force-publish --no-git-tag-version --yes
+          jlpm run set:workspace-version 9.8.7
           git commit -am "Release 9.8.7"
+          assert_release_state 9.8.7 9.8.7
 
-      - name: Patch Release
-        run: |
-          jlpm release:patch --force
+          jlpm release:bump next --skip-commit
+          assert_release_state 9.8.8 9.8.8
+          git restore .
 
-      - name: Minor Release
-        run: |
-          jlpm release:bump minor --force
+          jlpm release:patch
+          assert_release_state 9.8.8 9.8.8
+
+          jlpm release:bump minor
+          assert_release_state 9.9.0a0 9.9.0-alpha.0
+
+          jlpm release:bump next --skip-commit
+          assert_release_state 9.9.0a1 9.9.0-alpha.1
+          git restore .
+
+          jlpm release:bump release
+          assert_release_state 9.9.0b0 9.9.0-beta.0
+
+          jlpm release:bump release
+          assert_release_state 9.9.0rc0 9.9.0-rc.0
+
+          jlpm release:bump release
+          assert_release_state 9.9.0 9.9.0
 
-      - name: Release Cycle
+          jlpm release:bump major
+          assert_release_state 10.0.0a0 10.0.0-alpha.0
+
+      - name: Check dependency update helper
         run: |
-          # beta
-          jlpm release:bump release --force
-          # rc
-          jlpm release:bump release --force
-          # final
-          jlpm release:bump release --force
-
-      - name: Major Release
+          set -eux
+
+          UPDATE_LOG="$(
+            jlpm update:dependency @jupyterlab/application '~4.5.0-rc.1' --dry-run 2>&1
+          )"
+          printf '%s\n' "${UPDATE_LOG}"
+
+          grep -F 'packages/application/package.json' <<< "${UPDATE_LOG}"
+          grep -F 'packages/lab-extension/package.json' <<< "${UPDATE_LOG}"
+          git diff --exit-code
+
+      - name: Check JupyterLab version update helpers
         run: |
-          jlpm release:bump major --force
+          set -eux
+
+          EXACT_VERSION=$(node ./buildutils/lib/get-latest-lab-version.js --set-version v4.5.0rc1)
+          test "${EXACT_VERSION}" = "4.5.0rc1"
+
+          node ./buildutils/lib/upgrade-lab-dependencies.js --set-version 4.5.0rc1
+
+          grep -nF 'jupyterlab>=4.5.0rc1,<4.6' pyproject.toml .pre-commit-config.yaml
+          grep -nF '"@jupyterlab/application": "~4.5.0-rc.1"' app/package.json packages/lab-extension/package.json
+          git diff --name-only -- ui-tests/package.json | grep -Fx 'ui-tests/package.json'
 
   npm:
     runs-on: ubuntu-latest

diff --git a/.github/workflows/upgrade-jupyterlab-dependencies.yml b/.github/workflows/upgrade-jupyterlab-dependencies.yml
@@ -71,24 +71,40 @@ jobs:
 
           echo "latest=${LATEST}" >> $GITHUB_ENV
           jlpm upgrade:lab:dependencies --set-version ${LATEST}
-          if [[ ! -z "$(git status --porcelain package.json)" ]]; then
-            jlpm
-            jlpm deduplicate
 
-            cd ui-tests
-            jlpm
-            jlpm deduplicate
+      - name: Detect tracked changes
+        id: detect-changes
+        shell: bash
+        run: |
+          if [[ -n "$(git status --porcelain --untracked-files=no)" ]]; then
+            echo "has_changes=true" >> "$GITHUB_OUTPUT"
+          else
+            echo "has_changes=false" >> "$GITHUB_OUTPUT"
           fi
+
+      - name: Refresh JavaScript lockfiles
+        if: steps.detect-changes.outputs.has_changes == 'true'
+        run: |
+          jlpm
+          jlpm deduplicate
+
+          cd ui-tests
+          jlpm
+          jlpm deduplicate
+
       - uses: prefix-dev/setup-pixi@v0.9.4
+        if: steps.detect-changes.outputs.has_changes == 'true'
         with:
           pixi-version: v0.41.4
           manifest-path: pyproject.toml
           locked: false
 
       - name: Update pixi.lock
+        if: steps.detect-changes.outputs.has_changes == 'true'
         run: pixi install
 
       - name: Create a PR
+        if: steps.detect-changes.outputs.has_changes == 'true'
         env:
           GH_TOKEN: ${{ secrets.PERSONAL_GITHUB_TOKEN || secrets.GITHUB_TOKEN }}
         run: |
@@ -97,32 +113,34 @@ jobs:
           export LATEST=${{ env.latest }}
           export BRANCH_NAME=update-to-v${LATEST}
 
-          # if resulted in any change:
-          if [[ ! -z "$(git status --porcelain package.json)" ]]; then
-            # if branch already exists.
-            if git ls-remote --heads origin | grep "refs/heads/${BRANCH_NAME}$" > /dev/null; then
-              echo "Branch '${BRANCH_NAME}' exists."
-            else
-              # new branch is created
-              git checkout -b "${BRANCH_NAME}"
-              git config user.name "github-actions[bot]"
-              git config user.email 'github-actions[bot]@users.noreply.github.com'
+          if [[ -z "$(git status --porcelain --untracked-files=no)" ]]; then
+            echo "No tracked changes to commit."
+            exit 0
+          fi
 
-              git commit . -m "Update to JupyterLab v${LATEST}"
+          # if branch already exists.
+          if git ls-remote --heads origin | grep "refs/heads/${BRANCH_NAME}$" > /dev/null; then
+            echo "Branch '${BRANCH_NAME}' exists."
+          else
+            # new branch is created
+            git checkout -b "${BRANCH_NAME}"
+            git config user.name "github-actions[bot]"
+            git config user.email 'github-actions[bot]@users.noreply.github.com'
 
-              git push --set-upstream origin "${BRANCH_NAME}"
+            git commit . -m "Update to JupyterLab v${LATEST}"
 
-              PR_ARGS=(
-                --base "${{ inputs.branch || 'main' }}"
-                --title "Update to JupyterLab v${LATEST}"
-                --body "New JupyterLab release [v${LATEST}](https://github.com/jupyterlab/jupyterlab/releases/tag/v${LATEST}) is available. Please review the lock file carefully."
-              )
+            git push --set-upstream origin "${BRANCH_NAME}"
 
-              # Add --repo flag only if target_repo is specified
-              if [[ -n "${{ inputs.target_repo }}" ]]; then
-                PR_ARGS+=(--repo "${{ inputs.target_repo }}")
-              fi
+            PR_ARGS=(
+              --base "${{ inputs.branch || 'main' }}"
+              --title "Update to JupyterLab v${LATEST}"
+              --body "New JupyterLab release [v${LATEST}](https://github.com/jupyterlab/jupyterlab/releases/tag/v${LATEST}) is available. Please review the lock file carefully."
+            )
 
-              gh pr create "${PR_ARGS[@]}"
+            # Add --repo flag only if target_repo is specified
+            if [[ -n "${{ inputs.target_repo }}" ]]; then
+              PR_ARGS+=(--repo "${{ inputs.target_repo }}")
             fi
+
+            gh pr create "${PR_ARGS[@]}"
           fi
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
@@ -137,27 +137,6 @@ Running the end to end tests in headful mode will trigger something like the fol
 
 ![playwright-headed-demo](https://user-images.githubusercontent.com/591645/141274633-ca9f9c2f-eef6-430e-9228-a35827f8133d.gif)
 
-## Tasks caching
-
-The repository is configured to use the Lerna caching system (via `nx`) for some of the development scripts.
-
-This helps speed up rebuilds when running `jlpm run build` multiple times to avoid rebuilding packages that have not changed on disk.
-
-You can generate a graph to have a better idea of the dependencies between all the packages using the following command:
-
-```
-npx nx graph
-```
-
-Running the command will open a browser tab by default with a graph that looks like the following:
-
-![a screenshot showing the nx task graph](https://github.com/jupyter/notebook/assets/591645/34eb46f0-b0e5-44b6-9430-ae5fbd673a4b)
-
-To learn more about Lerna caching:
-
-- https://lerna.js.org/docs/features/cache-tasks
-- https://nx.dev/docs/features/cache-task-results
-
 ### Updating reference snapshots
 
 Often a PR might make changes to the user interface, which can cause the visual regression tests to fail.

diff --git a/app/package.json b/app/package.json
@@ -196,7 +196,6 @@
   },
   "devDependencies": {
     "@jupyterlab/builder": "~4.6.0-alpha.4",
-    "@jupyterlab/buildutils": "~4.6.0-alpha.4",
     "@rspack/cli": "^1.7.1",
     "@rspack/core": "^1.7.1",
     "@types/rimraf": "^3.0.2",