This project follows the Read the Docs code of conduct. If you are not familiar with our code of conduct policy, take a minute to read the policy before starting with your first contribution.

Modifying the theme

The styles for this theme use SASS and a custom CSS framework called Wyrm. We use Webpack and node-sass to build the CSS. Webpack is used to watch for changes, rebuild the static assets, and rebuild the Sphinx demo documentation.


The installation of Node is outside the scope of this documentation. You will need Node version 10+ in order to make changes to this theme.

Set up your environment

  1. Install Sphinx and documentation build dependencies.

    $ pip install -e '.[dev]'
  2. Install Webpack, node-sass, and theme dependencies locally.

    $ npm install

Making changes

Changes to the theme can be compiled and tested with Webpack:

$ npm run dev

This script will do the following:

  1. Install and update any dependencies.

  2. Build the static CSS from SASS source files.

  3. Build the demo documentation.

  4. Watch for changes to the SASS files and documentation and rebuild everything on any detected changes.

Alternatively, if you don’t need to watch the files, the release build script can be used to test built assets:

$ npm run build


QA testing theme changes and pull requests is complex, due to backwards compatibility.

The following cases need to be tested with changes to CSS or JavaScript:

  • Multiple, modern browsers should be tested. We officially support back to IE11 at the moment

  • Multiple viewport sizes should be tested for changes. We support large, tablet, and mobile viewport sizes

  • We currently support both the Sphinx HTML4 writer and HTML5 writer. This makes for some complex CSS selectors

  • Multiple major versions of Sphinx should be tested. We currently support back to Sphinx version 1.6

It’s easiest to test combinations of dependency versions using tox:

% tox -e py3-sphinx34-html4

If the tests and build are successful, you can view the built documentation at the directory noted by Sphinx:

build succeeded, 10 warnings.

The HTML pages are in .tox/py3-sphinx34-html4/tmp/html.
___________________________ summary ___________________________
  py3-sphinx34-html4: commands succeeded
  congratulations :)

You can then open up this path with a series of browsers to test.

The best way to spot UI issues is to compare two or more builds. You can build multiple tox environments, and open both up for comparison:

% tox -e py3-sphinx34-html4
% tox -e py3-sphinx34-html5
% firefox .tox/py3-sphinx34-html4/tmp/html/index.html
% firefox .tox/py3-sphinx34-html5/tmp/html/index.html

You can also use a separate tox environment for building output to compare against. All of the tox environments have an additional postfix, -qa, to allow building the same environment twice, without overwriting any files. In this test scenario, you would build from a branch or tag before building the same tox environment for the pull request branch you are testing.

For example, to test against the tag 0.5.2:

% git checkout 0.5.2
% tox -e py3-sphinx34-html4-qa
% git checkout feature/example-pull-request
% tox -e py3-sphinx34-html4
% firefox .tox/py3-sphinx34-html4-qa/tmp/html/index.html
% firefox .tox/py3-sphinx34-html4/tmp/html/index.html

Currently, the most important environments to QA are:

  • py3-sphinx18-html4

  • py3-sphinx18-html5

  • py3-sphinx24-html4

  • py3-sphinx24-html5

  • py3-sphinx35-html4

  • py3-sphinx35-html5

  • py3-sphinx41-html4

  • py3-sphinx41-html5


Translations are managed using Transifex. You can join any of the existing language teams or request a new language is added to the project. For more information on our translation standards, see our docs on Internationalization

Periodically, core team should update the translation files outside our normal releases. Someone from the core team, with write access to Transifex, should run the following:

$ python update_translations

This will extract new messages, upload the messages to Transifex, and will update our local translation files. Changes can be checked in to a branch and put up for review.

Releasing the theme

To release a new version of the theme, core team will take the following steps:

  1. Bump the version by running bump2version [major|minor|patch|dev]. This will automatically increase the correct part(s) of the version number, you do not need to specify the exact version number. We follow semantic versioning and PEP440 (with regards to alpha release and development versions). The version increment should reflect these releases and any potentially breaking changes.

  2. New versions are by default alpha releases. If this is a release candidate, run bump2version --allow-dirty release to update the release to an rc release. If this is a final release, run the command again.

  3. Update the changelog (docs/changelog.rst) with the version information.

  4. Run python update_translations to compile new translation files and update Transifex.

  5. Run python build_assets to rebuild all the theme assets and the Python package.

  6. Commit these changes.

  7. Tag the release in git: git tag $NEW_VERSION.

  8. Push the tag to GitHub: git push --tags origin.

  9. Upload the package to PyPI:

    $ rm -rf dist/
    $ python sdist bdist_wheel
    $ twine upload --sign --identity dist/*
  10. Finally, open a new pull request updating the development release version to the next patch by running bump2version patch. Open a pull request with this change.