Thank you for contributing to Voici!

Make sure to follow Project Jupyter’s Code of Conduct for a friendly and welcoming collaborative environment.

Setting up a development environment#

Note: You will need NodeJS to build the extension package.

Note: we recommend using mamba to speed the creating of the environment.

# create a new environment
mamba env create -f environment.yml

# activate the environment
mamba activate voici-dev

# Install package in development mode
pip install -e python/voici-core
pip install -e python/voici

voici follows a monorepo structure. To build all the packages at once:

yarn build

Then go to the demo folder and run the following command to build the demo application with Voici:

voici build --contents notebooks

Finally, run the following command to start the demo application:

python -m http.server --directory _output

Open a web browser and navigate to http://localhost:8000 to access the demo application.

UI Tests#

There are also end to end tests to cover higher level user interactions, located in the ui-tests folder. To run these tests:

cd ui-tests

# install dependencies

# install a browser
yarn playwright install chromium

# start the application
yarn start

# in another terminal, run the tests
yarn test

The test script calls the Playwright test runner. You can pass additional arguments to playwright by appending parameters to the command. For example to run the test in headed mode, jlpm test --headed.

Checkout the Playwright Command Line Reference for more information about the available command line options.

Updating reference snapshots#

Often a PR might make changes to the user interface, which can cause the visual regression tests to fail.

If you want to update the reference snapshots while working on a PR you can post the following sentence as a GitHub comment:

bot please update playwright snapshots

This will trigger a GitHub Action that will run the UI tests automatically and push new commits to the branch if the reference snapshots have changed.


First, follow the instructions above to set up a development environment.

Then, install the docs dependencies:

pip install myst-parser pydata-sphinx-theme sphinx sphinx-autobuild sphinxcontrib-video

Then, to build the documentation:

sphinx-build -W -b html docs docs/build/html

In a separate terminal, start the documentation server:

python -m http.server --directory docs/build/html

You can also build and watch the documentation using the following command:

sphinx-autobuild -W -b html docs docs/build/html --host

Then open a web browser and navigate to http://localhost:8000 to access the documentation.

Contributing from the browser#

Alternatively you can also contribute to Voici without setting up a local environment, directly from a web browser:

  • GitHub’s built-in editor is suitable for contributing small fixes

  • A more advanced editor can be accessed by pressing the dot (.) key while in the Voici GitHub repository,