How to contribute


If you want to start working on this project, you will need to get familiar with these APIs:

It is also recommended to take a look at these resources:

First steps

  1. Fork our repo, here’s the guide on forking

  2. Clone your new repo (forked repo) to have a local copy of the code

  3. Apply the required changes! See developer docs on how to work with the code

  4. Send a Pull Request to our original repo. Here’s the helpful guide on how to do that

Developer’s documentation

Make sure that you are familiar with developer’s documentation.

That’s a main starting point to the future development. You can jump start into the development of new rules by reading “Creating a new rule tutorial”.


We use poetry to manage the dependencies.

To install them you would need to run install command:

poetry install

To activate your virtualenv run poetry shell.

Adding new flake8 plugins

If you are adding a flake8 plugin dependency (not dev-dependency), you will have to do several things:

  1. Install plugin with poetry

  2. Add docs about the error code to the pages/usage/violations/index.rst

  3. Add a test that the plugin is working to tests/

One magic command

Run make test to run everything we have!

Building on Windows

  • Building directly in Windows does not work.

  • Instead, use a Windows Subsystem for Linux (WSL) such as Ubuntu 18.04 LTS that you can get from the Microsoft Store.

  • Clone the project to a part of the WSL where Windows does not overwrite permissions, for example directly to the home of the WSL (do cd and then git clone). That problem looks like this and you can read more about why changing the permissions does not work here.


We use pytest and flake8 for quality control. We also use wemake_python_styleguide itself to develop wemake_python_styleguide.

To run all tests:


To run linting:

flake8 .

These steps are mandatory during the CI.


We use import-linter to enforce strict layered architecture.


See .importlinter file for contracts definition. All contracts must be valid for each commit. This step is mandatory during the CI.

Type checks

We use mypy to run type checks on our code. To use it:

mypy wemake_python_styleguide

This step is mandatory during the CI.


This project is developed by a diverse and multilingual group of people. Many of us are not English native speakers and we also know that people can make mistakes and typos even in the simplest of words.

So, that’s why we use a bunch of tools to find and fix spelling and grammar.

You will need to install them manually, because we don’t ship them with the dependencies:

pip install codespell flake8-spellcheck

And then you can use them:

# codespell:
codespell -w wemake_python_styleguide tests docs scripts styles *.md

# flake8-spellcheck:
flake8 --whitelist ./tests/whitelist.txt .

We run them from time to time, this is not in the CI yet.


We also have several helpers to make your development work easier:

  • astboom is used to visualize ast nodes in other python modules, usage: astboom ast <

  • tokelor is used to visualize tokens in other python modules, usage: tokelor

Submitting your code

We use trunk based development (we also sometimes call it wemake-git-flow).

What the point of this method?

  1. We use protected master branch, so the only way to push your code is via pull request

  2. We use issue branches: to implement a new feature or to fix a bug create a new branch named issue-$TASKNUMBER

  3. Then create a pull request to master branch

  4. We use git tags to make releases, so we can track what has changed since the latest release

So, this way we achieve an easy and scalable development process which frees us from merging hell and long-living branches.

In this method, the latest version of the app is always in the master branch.

Before submitting

Before submitting your code please do the following steps:

  1. Run pytest to make sure everything was working before

  2. Add any changes you want

  3. Add tests for the new changes

  4. Add an integration test into tests/fixtures/

  5. Edit documentation if you have changed something significant

  6. Update with a quick summary of your changes

  7. Run pytest again to make sure it is still working

  8. Run mypy to ensure that types are correct

  9. Run flake8 to ensure that style is correct

  10. Run lint-imports to ensure that architecture contracts are correct

  11. Run doc8 to ensure that docs are correct

You can run everything at once with make test, see our Makefile for more details.

Notes for maintainers

This section is intended for maintainers only. If you are not a maintainer (or do not know what it means), just skip it. You are not going to miss anything useful.

Releasing a new version

Releasing a new version requires several steps:

  1. Ensure that is up-to-date and contains all changes

  2. Bump version in pyproject.toml

  3. Bump version in Dockerfile that is used for Github Action

  4. Run git commit -a -m 'Version x.y.z release' && git tag -a x.y.x -m 'Version x.y.z' && git push && git push --tags

  5. Run poetry publish --build

  6. Edit Github Release and mark that new action version is released

Done! New version is released.

Making patches to older versions

If you want to release a patch for an older version, that what you have to do:

  1. Check out the previous tag

  2. Create a new branch relative to this tag: git checkout $TAG_NAME; git checkout -b $RELEASE_NAME

  3. Merge it into master, there might be some rebase and cherry-pick involved during this operation

Other help

You can contribute by spreading a word about this library. It would also be a huge contribution to write a short article on how you are using this project. You can also share your best practices with us.

You can also consider donations to the project:

Number of current supporters:


List of contributors

Here are the awesome people who contributed to our project:

List of contributors