diff --git a/.github/workflows/check-tests.yml b/.github/workflows/check-tests.yml
new file mode 100644
index 00000000..36f0f91f
--- /dev/null
+++ b/.github/workflows/check-tests.yml
@@ -0,0 +1,71 @@
+name: Tests validation
+
+on:
+  push:
+    branches: ["*.0"]
+  pull_request:
+    branches: ["*"]
+  schedule:
+    - cron: "0 0 * * *"
+
+jobs:
+  tests:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Base Setup
+        uses: jupyterlab/maintainer-tools/.github/actions/base-setup@v1
+
+      - name: Install dependencies
+        run: python -m pip install -U cookiecutter check-manifest jupyterlab~=3.1
+
+      - name: Create the extension
+        run: |
+          set -eux
+          python -m cookiecutter --no-input .
+
+      - name: Test the extension
+        working-directory: myextension
+        run: |
+          set -eux
+          jlpm
+          jlpm test
+
+      - name: Install the extension
+        working-directory: myextension
+        run: |
+          set -eux
+          python -m pip install .
+
+      - name: Install dependencies
+        working-directory: myextension/ui-tests
+        env:
+          PLAYWRIGHT_SKIP_BROWSER_DOWNLOAD: 1
+        run: jlpm install
+        
+      - name: Set up browser cache
+        uses: actions/cache@v2
+        with:
+          path: |
+            ${{ github.workspace }}/pw-browsers
+          key: ${{ runner.os }}-${{ hashFiles('myextension/ui-tests/yarn.lock') }}
+          
+      - name: Install browser
+        run: jlpm playwright install chromium
+        working-directory: myextension/ui-tests
+
+      - name: Execute integration tests
+        working-directory: myextension/ui-tests
+        run: |
+          jlpm playwright test
+
+      - name: Upload Playwright Test report
+        if: always()
+        uses: actions/upload-artifact@v2
+        with:
+          name: myextension-playwright-tests
+          path: |
+            myextension/ui-tests/test-results
+            myextension/ui-tests/playwright-report
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 478c0b0e..532040ac 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -30,7 +30,7 @@ jobs:
 
       - name: Install dependencies
         run: |
-          python -m pip install cookiecutter check-manifest build
+          python -m pip install cookiecutter check-manifest
 
       - name: Create pure frontend extension
         env:
@@ -39,20 +39,20 @@ jobs:
         run: |
           set -eux
           # Trick to use custom parameters
-          python -c "from cookiecutter.main import cookiecutter; import json, os; f=open('cookiecutter.json'); d=json.load(f); f.close(); d['labextension_name']=os.getenv('NAME'); cookiecutter('.', extra_context=d, no_input=True)"
+          python -c "from cookiecutter.main import cookiecutter; import json, os; f=open('cookiecutter.json'); d=json.load(f); f.close(); d['kind']=d['kind'][0]; d['labextension_name']=os.getenv('NAME'); cookiecutter('.', extra_context=d, no_input=True)"
           pushd ${PYNAME}
-          pip install jupyterlab
+          python -m pip install jupyterlab
           jlpm
           jlpm stylelint-config-prettier-check
           jlpm lint:check
-          pip install -e .
+          python -m pip install -e .
           jupyter labextension develop . --overwrite
           jupyter labextension list
           jupyter labextension list 2>&1 | grep -ie "${NAME}.*OK"
           python -m jupyterlab.browser_check
 
           jupyter labextension uninstall ${NAME}
-          pip uninstall -y ${NAME} jupyterlab
+          python -m pip uninstall -y ${NAME} jupyterlab
 
           git init && git add .
           check-manifest -v
@@ -60,6 +60,48 @@ jobs:
           popd
           rm -rf ${NAME}
 
+  no-tests:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        # This will be used by the base setup action
+        python-version: ["3.10"]
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Base Setup
+        uses: jupyterlab/maintainer-tools/.github/actions/base-setup@v1
+
+      - name: Install dependencies
+        run: |
+          python -m pip install cookiecutter check-manifest
+
+      - name: Create pure frontend extension
+        run: |
+          set -eux
+          # Trick to use custom parameters
+          python -c "from cookiecutter.main import cookiecutter; import json; f=open('cookiecutter.json'); d=json.load(f); f.close(); d['kind']=d['kind'][0]; d['test']='n'; cookiecutter('.', extra_context=d, no_input=True)"
+          pushd myextension
+          pip install jupyterlab
+          jlpm
+          jlpm lint:check
+          pip install -e .
+          jupyter labextension develop . --overwrite
+          jupyter labextension list
+          jupyter labextension list 2>&1 | grep -ie "myextension.*OK"
+          python -m jupyterlab.browser_check
+
+          jupyter labextension uninstall myextension
+          pip uninstall -y myextension jupyterlab
+
+          git init && git add .
+          check-manifest -v
+
+          popd
+          rm -rf myextension
+
   settings:
     runs-on: ubuntu-latest
     strategy:
@@ -76,13 +118,13 @@ jobs:
 
       - name: Install dependencies
         run: |
-          python -m pip install cookiecutter check-manifest build
+          python -m pip install cookiecutter check-manifest
 
       - name: Create pure frontend extension
         run: |
           set -eux
           # Trick to use custom parameters
-          python -c "from cookiecutter.main import cookiecutter; import json; f=open('cookiecutter.json'); d=json.load(f); f.close(); d['has_settings']='y'; cookiecutter('.', extra_context=d, no_input=True)"
+          python -c "from cookiecutter.main import cookiecutter; import json; f=open('cookiecutter.json'); d=json.load(f); f.close(); d['kind']=d['kind'][0]; d['has_settings']='y'; cookiecutter('.', extra_context=d, no_input=True)"
           pushd myextension
           pip install jupyterlab
           jlpm
@@ -154,11 +196,14 @@ jobs:
           # Trick to use custom parameters
           python -c "from cookiecutter.main import cookiecutter; import json; f=open('cookiecutter.json'); d=json.load(f); f.close(); d['kind']='server'; cookiecutter('.', extra_context=d, no_input=True)"
           cd myextension
-          pip install -e .
-          pip install jupyterlab
+          python -m pip install -e .[test]
+          python -m pip install jupyterlab
           jupyter labextension develop . --overwrite
           jupyter server extension enable myextension
 
+          # Check unit tests are passing
+          python -m pytest -vv -r ap --cov myextension
+
       - name: Check pip develop method
         run: |
           set -eux
@@ -177,7 +222,7 @@ jobs:
           jupyter labextension build ./myextension
 
           jupyter labextension uninstall myextension
-          pip uninstall -y myextension jupyterlab
+          python -m pip uninstall -y myextension jupyterlab
 
           python -c "import shutil; shutil.rmtree('myextension')"
 
@@ -186,11 +231,11 @@ jobs:
           # Trick to use custom parameters
           python -c "from cookiecutter.main import cookiecutter; import json; f=open('cookiecutter.json'); d=json.load(f); f.close(); d['kind']='server'; cookiecutter('.', extra_context=d, no_input=True)"
           cd myextension
-          pip install jupyterlab
+          python -m pip install jupyterlab
           jupyter lab clean --all
           python -m build --sdist
           cd dist
-          pip install myextension-0.1.0.tar.gz
+          python -m pip install myextension-0.1.0.tar.gz
 
       - name: Check install tarball method
         run: |
@@ -205,7 +250,7 @@ jobs:
           python -m jupyterlab.browser_check
 
           cp myextension/dist/*.tar.gz myextension.tar.gz
-          pip uninstall -y myextension jupyterlab
+          python -m pip uninstall -y myextension jupyterlab
           rm -rf myextension
         shell: bash
 
@@ -248,8 +293,8 @@ jobs:
           sudo rm -rf $(which node)
           sudo rm -rf $(which node)
 
-          pip install myextension.tar.gz
-          pip install jupyterlab
+          python -m pip install myextension.tar.gz
+          python -m pip install jupyterlab
           jupyter labextension list 2>&1 | grep -ie "myextension.*OK"
           jupyter server extension list
           jupyter server extension list 2>&1 | grep -ie "myextension.*OK"
@@ -279,17 +324,17 @@ jobs:
           # Trick to use custom parameters
           python -c "from cookiecutter.main import cookiecutter; import json; f=open('cookiecutter.json'); d=json.load(f); f.close(); d['kind']='theme'; cookiecutter('.', extra_context=d, no_input=True)"
           pushd mytheme
-          pip install jupyterlab
+          python -m pip install jupyterlab
           jlpm
           jlpm lint:check
-          pip install -e .
+          python -m pip install -e .
           jupyter labextension develop . --overwrite
           jupyter labextension list
           jupyter labextension list 2>&1 | grep -ie "mytheme.*OK"
           python -m jupyterlab.browser_check
 
           jupyter labextension uninstall mytheme
-          pip uninstall -y mytheme jupyterlab
+          python -m pip uninstall -y mytheme jupyterlab
 
           git init && git add .
           check-manifest -v
diff --git a/cookiecutter.json b/cookiecutter.json
index 2c9a9368..16c4c9ba 100644
--- a/cookiecutter.json
+++ b/cookiecutter.json
@@ -7,5 +7,6 @@
   "project_short_description": "A JupyterLab extension.",
   "has_settings": "n",
   "has_binder": "n",
+  "test": "y",
   "repository": "https://github.com/github_username/{{ cookiecutter.labextension_name }}"
 }
diff --git a/hooks/post_gen_project.py b/hooks/post_gen_project.py
index 5600c3f5..58de3d4d 100644
--- a/hooks/post_gen_project.py
+++ b/hooks/post_gen_project.py
@@ -4,11 +4,14 @@
 PROJECT_DIRECTORY = Path.cwd()
 
 
-def remove_path(path: str) -> None:
+def remove_path(path: Path) -> None:
     """Remove the provided path.
     
     If the target path is a directory, remove it recursively.
     """
+    if not path.exists():
+        return
+
     if path.is_file():
         path.unlink()
     elif path.is_dir():
@@ -35,10 +38,21 @@ def remove_path(path: str) -> None:
         for f in (
             "{{ cookiecutter.python_name }}/handlers.py",
             "src/handler.ts",
-            "jupyter-config"
+            "jupyter-config",
+            "conftest.py",
+            "{{ cookiecutter.python_name }}/tests"
         ):
             remove_path(PROJECT_DIRECTORY / f)
 
     if not "{{ cookiecutter.has_binder }}".lower().startswith("y"):
         remove_path(PROJECT_DIRECTORY / "binder")
         remove_path(PROJECT_DIRECTORY / ".github/workflows/binder-on-pr.yml")
+
+    if not "{{ cookiecutter.test }}".lower().startswith("y"):
+        remove_path(PROJECT_DIRECTORY / ".github" / "workflows" / "update-integration-tests.yml")
+        remove_path(PROJECT_DIRECTORY / "src" / "__tests__")
+        remove_path(PROJECT_DIRECTORY / "ui-tests")
+        remove_path(PROJECT_DIRECTORY / "{{ cookiecutter.python_name }}" / "tests")
+        remove_path(PROJECT_DIRECTORY / "babel.config.js")
+        remove_path(PROJECT_DIRECTORY / "conftest.py")
+        remove_path(PROJECT_DIRECTORY / "jest.config.js")
diff --git a/{{cookiecutter.python_name}}/.eslintignore b/{{cookiecutter.python_name}}/.eslintignore
index 5c99ba78..fffa32fd 100644
--- a/{{cookiecutter.python_name}}/.eslintignore
+++ b/{{cookiecutter.python_name}}/.eslintignore
@@ -3,3 +3,6 @@ dist
 coverage
 **/*.d.ts
 tests
+
+**/__tests__
+ui-tests
diff --git a/{{cookiecutter.python_name}}/.github/workflows/build.yml b/{{cookiecutter.python_name}}/.github/workflows/build.yml
index 04557a93..cc8ca757 100644
--- a/{{cookiecutter.python_name}}/.github/workflows/build.yml
+++ b/{{cookiecutter.python_name}}/.github/workflows/build.yml
@@ -9,6 +9,7 @@ on:
 jobs:
   build:
     runs-on: ubuntu-latest
+
     steps:
     - name: Checkout
       uses: actions/checkout@v2
@@ -19,30 +20,45 @@ jobs:
     - name: Install dependencies
       run: python -m pip install -U jupyterlab~=3.1 check-manifest
 
-    - name: Build the extension
+    - name: Lint the extension
       run: |
         set -eux
         jlpm
-        jlpm lint:check
-        python -m pip install .
+        jlpm run lint:check
+{% if cookiecutter.test.lower().startswith('y') %}    
+    - name: Test the extension
+      run: |
+        set -eux
+        jlpm run test
+{% endif %}
+    - name: Build the extension
+      run: |
+        set -eux
+        python -m pip install .[test]
 {% if cookiecutter.kind.lower() == 'server' %}
+        pytest -vv -r ap --cov {{ cookiecutter.python_name }}
+        jupyter server extension list
         jupyter server extension list 2>&1 | grep -ie "{{ cookiecutter.python_name }}.*OK"
 {% endif %}
+        jupyter labextension list
         jupyter labextension list 2>&1 | grep -ie "{{ cookiecutter.labextension_name }}.*OK"
         python -m jupyterlab.browser_check
 
+    - name: Package the extension
+      run: |
+        set -eux
         check-manifest -v
 
         pip install build
-        python -m build --sdist
-        cp dist/*.tar.gz myextension.tar.gz
+        python -m build
         pip uninstall -y "{{ cookiecutter.python_name }}" jupyterlab
-        rm -rf myextension
 
-    - uses: actions/upload-artifact@v2
+    - name: Upload extension packages
+      uses: actions/upload-artifact@v2
       with:
-        name: myextension-sdist
-        path: myextension.tar.gz
+        name: extension-artifacts
+        path: dist/{{ cookiecutter.python_name }}*
+        if-no-files-found: error
 
   test_isolated:
     needs: build
@@ -54,18 +70,80 @@ jobs:
     - name: Install Python
       uses: actions/setup-python@v2
       with:
-        python-version: '3.8'
+        python-version: '3.9'
         architecture: 'x64'
     - uses: actions/download-artifact@v2
       with:
-        name: myextension-sdist
+        name: extension-artifacts
     - name: Install and Test
       run: |
         set -eux
         # Remove NodeJS, twice to take care of system and locally installed node versions.
         sudo rm -rf $(which node)
         sudo rm -rf $(which node)
-        pip install myextension.tar.gz
-        pip install jupyterlab
+
+        pip install "jupyterlab~=3.1" {{ cookiecutter.python_name }}*.whl
+
+{% if cookiecutter.kind.lower() == 'server' %}
+        jupyter server extension list
+        jupyter server extension list 2>&1 | grep -ie "{{ cookiecutter.python_name }}.*OK"
+{% endif %}
+        jupyter labextension list
         jupyter labextension list 2>&1 | grep -ie "{{ cookiecutter.labextension_name }}.*OK"
         python -m jupyterlab.browser_check --no-chrome-test
+{% if cookiecutter.test.lower().startswith('y') %}
+  integration-tests:
+    name: Integration tests
+    needs: build
+    runs-on: ubuntu-latest
+
+    env:
+      PLAYWRIGHT_BROWSERS_PATH: ${{ "{{ github.workspace }}" }}/pw-browsers
+
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v2
+
+    - name: Base Setup
+      uses: jupyterlab/maintainer-tools/.github/actions/base-setup@v1
+
+    - name: Download extension package
+      uses: actions/download-artifact@v2
+      with:
+        name: extension-artifacts
+        
+    - name: Install the extension
+      run: |
+        set -eux
+        python -m pip install "jupyterlab~=3.1" {{ cookiecutter.python_name }}*.whl
+
+    - name: Install dependencies
+      working-directory: ui-tests
+      env:
+        PLAYWRIGHT_SKIP_BROWSER_DOWNLOAD: 1
+      run: jlpm install
+{% raw %}
+    - name: Set up browser cache
+      uses: actions/cache@v2
+      with:
+        path: |
+          ${{ github.workspace }}/pw-browsers
+        key: ${{ runner.os }}-${{ hashFiles('ui-tests/yarn.lock') }}
+{% endraw %}
+    - name: Install browser
+      run: jlpm playwright install chromium
+      working-directory: ui-tests
+
+    - name: Execute integration tests
+      working-directory: ui-tests
+      run: |
+        jlpm playwright test
+
+    - name: Upload Playwright Test report
+      if: always()
+      uses: actions/upload-artifact@v2
+      with:
+        name: {{ cookiecutter.python_name }}-playwright-tests
+        path: |
+          ui-tests/test-results
+          ui-tests/playwright-report{% endif %}
diff --git a/{{cookiecutter.python_name}}/.github/workflows/update-integration-tests.yml b/{{cookiecutter.python_name}}/.github/workflows/update-integration-tests.yml
new file mode 100644
index 00000000..71a4c511
--- /dev/null
+++ b/{{cookiecutter.python_name}}/.github/workflows/update-integration-tests.yml
@@ -0,0 +1,44 @@
+name: Update Playwright Snapshots
+
+on:
+  issue_comment:
+    types: [created, edited]
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  {# Escape double curly brace #}
+  {% raw %}
+  update-snapshots:
+    if: ${{ github.event.issue.pull_request && contains(github.event.comment.body, 'please update playwright snapshots') }}
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Configure git to use https
+        run: git config --global hub.protocol https
+
+      - name: Checkout the branch from the PR that triggered the job
+        run: hub pr checkout ${{ github.event.issue.number }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Install dependencies
+        run: |
+          set -eux
+          jlpm
+          python -m pip install .
+
+      - uses: jupyterlab/maintainer-tools/.github/actions/update-snapshots@v1
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          # Playwright knows how to start JupyterLab server
+          start_server_script: 'null'
+          test_folder: ui-tests
+      {% endraw %}
\ No newline at end of file
diff --git a/{{cookiecutter.python_name}}/.gitignore b/{{cookiecutter.python_name}}/.gitignore
index f65e39ac..dd448c5c 100644
--- a/{{cookiecutter.python_name}}/.gitignore
+++ b/{{cookiecutter.python_name}}/.gitignore
@@ -8,6 +8,10 @@ node_modules/
 *.tsbuildinfo
 {{cookiecutter.python_name}}/labextension
 
+# Integration tests
+ui-tests/test-results/
+ui-tests/playwright-report/
+
 # Created by https://www.gitignore.io/api/python
 # Edit at https://www.gitignore.io/?templates=python
 
diff --git a/{{cookiecutter.python_name}}/MANIFEST.in b/{{cookiecutter.python_name}}/MANIFEST.in
index 9fa017c7..f7776de0 100644
--- a/{{cookiecutter.python_name}}/MANIFEST.in
+++ b/{{cookiecutter.python_name}}/MANIFEST.in
@@ -1,11 +1,13 @@
 include LICENSE
 include *.md
 include pyproject.toml{% if cookiecutter.kind == "server" %}
-recursive-include jupyter-config *.json{% endif %}
+recursive-include jupyter-config *.json{% endif %}{% if cookiecutter.test.lower().startswith('y') %}
+include conftest.py{% endif %}
 
 include package.json
 include install.json
-include ts*.json
+include ts*.json{% if cookiecutter.test.lower().startswith('y') %}
+include *.config.js{% endif %}
 include yarn.lock
 
 graft {{ cookiecutter.python_name }}/labextension
@@ -13,7 +15,8 @@ graft {{ cookiecutter.python_name }}/labextension
 # Javascript files
 graft src
 graft style{% if cookiecutter.has_settings.lower().startswith('y') %}
-graft schema{% endif %}
+graft schema{% endif %}{% if cookiecutter.test.lower().startswith('y') %}
+graft ui-tests{% endif %}
 prune **/node_modules
 prune lib
 prune binder
diff --git a/{{cookiecutter.python_name}}/README.md b/{{cookiecutter.python_name}}/README.md
index 8947613c..6d775be1 100644
--- a/{{cookiecutter.python_name}}/README.md
+++ b/{{cookiecutter.python_name}}/README.md
@@ -97,7 +97,43 @@ pip uninstall {{ cookiecutter.python_name }}
 In development mode, you will also need to remove the symlink created by `jupyter labextension develop`
 command. To find its location, you can run `jupyter labextension list` to figure out where the `labextensions`
 folder is located. Then you can remove the symlink named `{{ cookiecutter.labextension_name }}` within that folder.
+{% if cookiecutter.test.lower().startswith('y') %}
+### Testing the extension{% if cookiecutter.kind.lower() == 'server' %}
 
+#### Server tests
+
+This extension is using [Pytest](https://docs.pytest.org/) for Python code testing.
+
+Install test dependencies (needed only once):
+
+```sh
+pip install -e ".[test]"
+```
+
+To execute them, run:
+
+```sh
+pytest -vv -r ap --cov {{ cookiecutter.python_name }}
+```{% endif %}
+
+#### Frontend tests
+
+This extension is using [Jest](https://jestjs.io/) for JavaScript code testing.
+
+To execute them, execute:
+
+```sh
+jlpm
+jlpm test
+```
+
+#### Integration tests
+
+This extension uses [Playwright](https://playwright.dev/docs/intro/) for the integration tests (aka user level tests).
+More precisely, the JupyterLab helper [Galata](https://github.com/jupyterlab/jupyterlab/tree/master/galata) is used to handle testing the extension in JupyterLab.
+
+More information are provided within the [ui-tests](./ui-tests/README.md) README.
+{% endif %}
 ### Packaging the extension
 
 See [RELEASE](RELEASE.md)
diff --git a/{{cookiecutter.python_name}}/babel.config.js b/{{cookiecutter.python_name}}/babel.config.js
new file mode 100644
index 00000000..8b5c7642
--- /dev/null
+++ b/{{cookiecutter.python_name}}/babel.config.js
@@ -0,0 +1 @@
+module.exports = require('@jupyterlab/testutils/lib/babel.config');
diff --git a/{{cookiecutter.python_name}}/conftest.py b/{{cookiecutter.python_name}}/conftest.py
new file mode 100644
index 00000000..26d7ca5e
--- /dev/null
+++ b/{{cookiecutter.python_name}}/conftest.py
@@ -0,0 +1,8 @@
+import pytest
+
+pytest_plugins = ("jupyter_server.pytest_plugin", )
+
+
+@pytest.fixture
+def jp_server_config(jp_server_config):
+    return {"ServerApp": {"jpserver_extensions": {"{{ cookiecutter.python_name }}": True}}}
diff --git a/{{cookiecutter.python_name}}/jest.config.js b/{{cookiecutter.python_name}}/jest.config.js
new file mode 100644
index 00000000..514c3809
--- /dev/null
+++ b/{{cookiecutter.python_name}}/jest.config.js
@@ -0,0 +1,42 @@
+const jestJupyterLab = require('@jupyterlab/testutils/lib/jest-config');
+
+const esModules = [
+  '@jupyterlab/',
+  'lib0',
+  'y\\-protocols',
+  'y\\-websocket',
+  'yjs'
+].join('|');
+
+const jlabConfig = jestJupyterLab(__dirname);
+
+const {
+  moduleFileExtensions,
+  moduleNameMapper,
+  preset,
+  setupFilesAfterEnv,
+  setupFiles,
+  testPathIgnorePatterns,
+  transform
+} = jlabConfig;
+
+module.exports = {
+  moduleFileExtensions,
+  moduleNameMapper,
+  preset,
+  setupFilesAfterEnv,
+  setupFiles,
+  testPathIgnorePatterns,
+  transform,
+  automock: false,
+  collectCoverageFrom: ['src/**/*.{ts,tsx}', '!src/**/*.d.ts'],
+  coverageDirectory: 'coverage',
+  coverageReporters: ['lcov', 'text'],
+  globals: {
+    'ts-jest': {
+      tsconfig: 'tsconfig.json'
+    }
+  },
+  testRegex: 'src/.*/.*.spec.ts[x]?$',
+  transformIgnorePatterns: [`/node_modules/(?!${esModules}).+`]
+};
diff --git a/{{cookiecutter.python_name}}/package.json b/{{cookiecutter.python_name}}/package.json
index 3fdc1ab9..b59aa9fd 100644
--- a/{{cookiecutter.python_name}}/package.json
+++ b/{{cookiecutter.python_name}}/package.json
@@ -48,7 +48,8 @@
     "prettier:base": "prettier \"**/*{.ts,.tsx,.js,.jsx,.css,.json,.md}\"",
     "prettier:check": "jlpm prettier:base --check",
     "stylelint": "jlpm stylelint:check --fix",
-    "stylelint:check": "stylelint --cache \"style/**/*.css\"",
+    "stylelint:check": "stylelint --cache \"style/**/*.css\"",{% if cookiecutter.test.lower().startswith('y') %}
+    "test": "jest --coverage",{% endif %}
     "watch": "run-p watch:src watch:labextension",
     "watch:src": "tsc -w",
     "watch:labextension": "jupyter labextension watch ."
@@ -62,12 +63,17 @@
 {% endif %}
   },
   "devDependencies": {
-    "@jupyterlab/builder": "^3.1.0",
+    {% if cookiecutter.test.lower().startswith('y') %}"@babel/core": "^7.0.0",
+    "@babel/preset-env": "^7.0.0",
+    {% endif %}"@jupyterlab/builder": "^3.1.0",{% if cookiecutter.test.lower().startswith('y') %}
+    "@jupyterlab/testutils": "^3.0.0",
+    "@types/jest": "^26.0.0",{% endif %}
     "@typescript-eslint/eslint-plugin": "^4.8.1",
     "@typescript-eslint/parser": "^4.8.1",
     "eslint": "^7.14.0",
     "eslint-config-prettier": "^6.15.0",
-    "eslint-plugin-prettier": "^3.1.4",{% if cookiecutter.kind.lower() == 'server' %}
+    "eslint-plugin-prettier": "^3.1.4",{% if cookiecutter.test.lower().startswith('y') %}
+    "jest": "^26.0.0",{% endif %}{% if cookiecutter.kind.lower() == 'server' %}
     "mkdirp": "^1.0.3",{% endif %}
     "npm-run-all": "^4.1.5",
     "prettier": "^2.1.1",
@@ -77,7 +83,8 @@
     "stylelint-config-recommended": "^6.0.0",
     "stylelint-config-standard": "~24.0.0",
     "stylelint-prettier": "^2.0.0",
-    "typescript": "~4.1.3"
+    "typescript": "~4.1.3"{% if cookiecutter.test.lower().startswith('y') %},
+    "ts-jest": "^26.0.0"{% endif %}
   },
   "sideEffects": [
     "style/*.css"{% if cookiecutter.kind.lower() != 'theme' %},
diff --git a/{{cookiecutter.python_name}}/setup.py b/{{cookiecutter.python_name}}/setup.py
index 49dc72e5..72649139 100644
--- a/{{cookiecutter.python_name}}/setup.py
+++ b/{{cookiecutter.python_name}}/setup.py
@@ -55,10 +55,19 @@
     license_file="LICENSE",
     long_description=long_description,
     long_description_content_type="text/markdown",
-    packages=setuptools.find_packages(),
-    install_requires=[{% if cookiecutter.kind.lower() == "server" %}
+    packages=setuptools.find_packages(),{% if cookiecutter.kind.lower() == "server" %}
+    install_requires=[
         "jupyter_server>=1.6,<2"
-    {% endif %}],
+    ],
+    extras_require={
+        "test": [{% if cookiecutter.test.lower().startswith('y') %}
+            "coverage",
+            "pytest",
+            "pytest-asyncio",
+            "pytest-cov",
+            "pytest-tornasync"
+        {% endif %}]
+    },{% endif %}
     zip_safe=False,
     include_package_data=True,
     python_requires=">=3.7",
diff --git a/{{cookiecutter.python_name}}/src/__tests__/{{cookiecutter.python_name}}.spec.ts b/{{cookiecutter.python_name}}/src/__tests__/{{cookiecutter.python_name}}.spec.ts
new file mode 100644
index 00000000..244d0548
--- /dev/null
+++ b/{{cookiecutter.python_name}}/src/__tests__/{{cookiecutter.python_name}}.spec.ts
@@ -0,0 +1,9 @@
+/**
+ * Example of [Jest](https://jestjs.io/docs/getting-started) unit tests
+ */
+
+describe('{{ cookiecutter.labextension_name }}', () => {
+  it('should be tested', () => {
+    expect(1 + 1).toEqual(2);
+  });
+});
diff --git a/{{cookiecutter.python_name}}/tsconfig.json b/{{cookiecutter.python_name}}/tsconfig.json
index b9c465a8..c8eb70e6 100644
--- a/{{cookiecutter.python_name}}/tsconfig.json
+++ b/{{cookiecutter.python_name}}/tsconfig.json
@@ -18,7 +18,7 @@
     "strict": true,
     "strictNullChecks": true,
     "target": "es2017",
-    "types": []
+    "types": [{% if cookiecutter.test.lower().startswith('y') %}"jest"{% endif %}]
   },
   "include": ["src/*"]
 }
diff --git a/{{cookiecutter.python_name}}/ui-tests/README.md b/{{cookiecutter.python_name}}/ui-tests/README.md
new file mode 100644
index 00000000..faef1bd3
--- /dev/null
+++ b/{{cookiecutter.python_name}}/ui-tests/README.md
@@ -0,0 +1,149 @@
+# Integration Testing
+
+This folder contains the integration tests of the extension.
+
+They are defined using [Playwright](https://playwright.dev/docs/intro/) test runner
+and [Galata](https://github.com/jupyterlab/jupyterlab/tree/master/galata) helper.
+
+The Playwright configuration is defined in [playwright.config.js](../playwright.config.js)
+in the root directory.
+
+The JupyterLab server configuration to use for the integration test is defined
+in [jupyter_server_test_config.py](../jupyter_server_test_config.py) in the root directory.
+
+The default configuration will produce video for failing tests and an HTML report.
+
+## Run the tests
+
+> All commands are assumed to be executed from the root directory
+
+To run the tests, you need to:
+
+1. Compile the extension:
+
+```sh
+jlpm install
+jlpm build:prod
+```
+
+> Check the extension is installed in JupyterLab.
+
+2. Install test dependencies (needed only once):
+
+```sh
+cd ./ui-tests
+jlpm install
+jlpm playwright install
+cd ..
+```
+
+3. Execute the [Playwright](https://playwright.dev/docs/intro) tests:
+
+```sh
+cd ./ui-tests
+jlpm playwright test
+```
+
+Test results will be shown in the terminal. In case of any test failures, the test report
+will be opened in your browser at the end of the tests execution; see
+[Playwright documentation](https://playwright.dev/docs/test-reporters#html-reporter)
+for configuring that behavior.
+
+## Update the tests snapshots
+
+> All commands are assumed to be executed from the root directory
+
+If you are comparing snapshots to validate your tests, you may need to update
+the reference snapshots stored in the repository. To do that, you need to:
+
+1. Compile the extension:
+
+```sh
+jlpm install
+jlpm build:prod
+```
+
+> Check the extension is installed in JupyterLab.
+
+2. Install test dependencies (needed only once):
+
+```sh
+cd ./ui-tests
+jlpm install
+jlpm playwright install
+cd ..
+```
+
+3. Execute the [Playwright](https://playwright.dev/docs/intro) command:
+
+```sh
+cd ./ui-tests
+jlpm playwright test -u
+```
+
+> Some discrepancy may occurs between the snapshots generated on your computer and
+> the one generated on the CI. To ease updating the snapshots on a PR, you can
+> type `please update playwright snapshots` to trigger the update by a bot on the CI.
+> Once the bot has computed new snapshots, it will commit them to the PR branch.
+
+## Create tests
+
+> All commands are assumed to be executed from the root directory
+
+To create tests, the easiest way is to use the code generator tool of playwright:
+
+1. Compile the extension:
+
+```sh
+jlpm install
+jlpm build:prod
+```
+
+> Check the extension is installed in JupyterLab.
+
+2. Install test dependencies (needed only once):
+
+```sh
+cd ./ui-tests
+jlpm install
+jlpm playwright install
+cd ..
+```
+
+3. Execute the [Playwright code generator](https://playwright.dev/docs/codegen):
+
+```sh
+cd ./ui-tests
+jlpm playwright codegen localhost:8888
+```
+
+## Debug tests
+
+> All commands are assumed to be executed from the root directory
+
+To debug tests, a good way is to use the inspector tool of playwright:
+
+1. Compile the extension:
+
+```sh
+jlpm install
+jlpm build:prod
+```
+
+> Check the extension is installed in JupyterLab.
+
+2. Install test dependencies (needed only once):
+
+```sh
+cd ./ui-tests
+jlpm install
+jlpm playwright install
+cd ..
+```
+
+3. Execute the Playwright tests in [debug mode](https://playwright.dev/docs/debug):
+
+```sh
+cd ./ui-tests
+PWDEBUG=1 jlpm playwright test
+```
diff --git a/{{cookiecutter.python_name}}/ui-tests/jupyter_server_test_config.py b/{{cookiecutter.python_name}}/ui-tests/jupyter_server_test_config.py
new file mode 100644
index 00000000..5ba7a914
--- /dev/null
+++ b/{{cookiecutter.python_name}}/ui-tests/jupyter_server_test_config.py
@@ -0,0 +1,20 @@
+"""Server configuration for integration tests.
+
+!! Never use this configuration in production because it
+opens the server to the world and provide access to JupyterLab
+JavaScript objects through the global window variable.
+"""
+from tempfile import mkdtemp
+
+c.ServerApp.port = 8888
+c.ServerApp.port_retries = 0
+c.ServerApp.open_browser = False
+
+c.ServerApp.root_dir = mkdtemp(prefix='galata-test-')
+c.ServerApp.token = ""
+c.ServerApp.password = ""
+c.ServerApp.disable_check_xsrf = True
+c.LabApp.expose_app_in_browser = True
+
+# Uncomment to set server log level to debug level
+# c.ServerApp.log_level = "DEBUG"
diff --git a/{{cookiecutter.python_name}}/ui-tests/package.json b/{{cookiecutter.python_name}}/ui-tests/package.json
new file mode 100644
index 00000000..0b57eebb
--- /dev/null
+++ b/{{cookiecutter.python_name}}/ui-tests/package.json
@@ -0,0 +1,13 @@
+{
+  "name": "{{ cookiecutter.labextension_name }}-ui-tests",
+  "version": "1.0.0",
+  "description": "JupyterLab {{ cookiecutter.labextension_name }} Integration Tests",
+  "private": true,
+  "scripts": {
+    "start": "jupyter lab --config jupyter_server_test_config.py",
+    "test": "jlpm playwright test"
+  },
+  "devDependencies": {
+    "@jupyterlab/galata": "^4.3.0"
+  }
+}
diff --git a/{{cookiecutter.python_name}}/ui-tests/playwright.config.js b/{{cookiecutter.python_name}}/ui-tests/playwright.config.js
new file mode 100644
index 00000000..9ece6fa1
--- /dev/null
+++ b/{{cookiecutter.python_name}}/ui-tests/playwright.config.js
@@ -0,0 +1,14 @@
+/**
+ * Configuration for Playwright using default from @jupyterlab/galata
+ */
+const baseConfig = require('@jupyterlab/galata/lib/playwright-config');
+
+module.exports = {
+  ...baseConfig,
+  webServer: {
+    command: 'jlpm start',
+    url: 'http://localhost:8888/lab',
+    timeout: 120 * 1000,
+    reuseExistingServer: !process.env.CI
+  }
+};
diff --git a/{{cookiecutter.python_name}}/ui-tests/tests/{{cookiecutter.python_name}}.spec.ts b/{{cookiecutter.python_name}}/ui-tests/tests/{{cookiecutter.python_name}}.spec.ts
new file mode 100644
index 00000000..a0c95499
--- /dev/null
+++ b/{{cookiecutter.python_name}}/ui-tests/tests/{{cookiecutter.python_name}}.spec.ts
@@ -0,0 +1,21 @@
+import { expect, test } from '@jupyterlab/galata';
+
+/**
+ * Don't load JupyterLab webpage before running the tests.
+ * This is required to ensure we capture all log messages.
+ */
+test.use({ autoGoto: false });
+
+test('should emit an activation console message', async ({ page }) => {
+  const logs: string[] = [];
+
+  page.on('console', message => {
+    logs.push(message.text());
+  });
+
+  await page.goto();
+
+  expect(
+    logs.filter(s => s === 'JupyterLab extension {{ cookiecutter.labextension_name }} is activated!')
+  ).toHaveLength(1);
+});
diff --git a/{{cookiecutter.python_name}}/{{cookiecutter.python_name}}/tests/__init__.py b/{{cookiecutter.python_name}}/{{cookiecutter.python_name}}/tests/__init__.py
new file mode 100644
index 00000000..edc5557d
--- /dev/null
+++ b/{{cookiecutter.python_name}}/{{cookiecutter.python_name}}/tests/__init__.py
@@ -0,0 +1 @@
+"""Python unit tests for {{ cookiecutter.python_name }}."""
diff --git a/{{cookiecutter.python_name}}/{{cookiecutter.python_name}}/tests/test_handlers.py b/{{cookiecutter.python_name}}/{{cookiecutter.python_name}}/tests/test_handlers.py
new file mode 100644
index 00000000..f8df064b
--- /dev/null
+++ b/{{cookiecutter.python_name}}/{{cookiecutter.python_name}}/tests/test_handlers.py
@@ -0,0 +1,13 @@
+import json
+
+
+async def test_get_example(jp_fetch):
+    # When
+    response = await jp_fetch("{{ cookiecutter.python_name | replace('_', '-') }}", "get_example")
+
+    # Then
+    assert response.code == 200
+    payload = json.loads(response.body)
+    assert payload == {
+        "data": "This is /{{ cookiecutter.python_name | replace('_', '-') }}/get_example endpoint!"
+    }
\ No newline at end of file