tox-gh-actions is a tox plugin which helps running tox on GitHub Actions with multiple different Python versions on multiple workers in parallel. This project is inspired by tox-travis.

• Features
• Usage
• Examples
  • Basic Example
    • tox-gh-actions Configuration
    • Workflow Configuration
  • Advanced Examples
    • Factor-Conditional Settings: Python Version
    • Factor-Conditional Settings: Environment Variable
    • tox requires
  • Overriding Environments to Run
• Versioning
• Versions and Compatibility
• Understanding Behavior of tox-gh-actions
  • How tox-gh-actions Works
  • Logging

When running tox on GitHub Actions, tox-gh-actions

• detects which environment to run based on configurations and
• provides utilities such as grouping log lines.

1. Add configurations under [gh-actions] section along with tox's configuration.

   • It will be pyproject.toml, tox.ini, or setup.cfg. See tox's documentation for more details.

2. Install tox-gh-actions package in the GitHub Actions workflow before running tox command.

The following configuration will create 3 jobs when running the workflow on GitHub Actions.

• On Python 3.10 job, tox runs py310 environment
• On Python 3.12 job, tox runs py312 environment
• On Python 3.14 job, tox runs py314 and mypy environments

Add [gh-actions] section to the same file as tox's configuration.

If you're using tox.ini:

[tox]
envlist = py310, py312, py314, mypy

[gh-actions]
python =
    3.10: py310
    3.12: py312
    3.14: py314, mypy

[testenv]
...

If you're using setup.cfg:

[tox:tox]
envlist = py310, py312, py314, mypy

[gh-actions]
python =
    3.10: py310
    3.12: py312
    3.14: py314, mypy

[testenv]
...

If you're using pyproject.toml:

[tool.tox]
legacy_tox_ini = """
[tox]
envlist = py310, py312, py314, mypy

[gh-actions]
python =
    3.10: py310
    3.12: py312
    3.14: py314, mypy

[testenv]
"""

.github/workflows/<workflow>.yml:

name: Python package

on:
  - push
  - pull_request

jobs:
  build:
    runs-on: ubuntu-latest
    strategy:
      matrix:
        python-version: ['3.10', '3.12', '3.14']

    steps:
    - uses: actions/checkout@v5
    - name: Set up Python ${{ matrix.python-version }}
      uses: actions/setup-python@v6
      with:
        python-version: ${{ matrix.python-version }}
    - name: Install dependencies
      run: |
        python -m pip install --upgrade pip
        python -m pip install tox tox-gh-actions
    - name: Test with tox
      run: tox

The following configuration will create 2 jobs when running the workflow on GitHub Actions.

• On Python 3.12 job, tox runs py12-django42 environment
• On Python 3.13 job, tox runs py313-django42 and py313-django52 environments

tox.ini:

[tox]
envlist = py312-django42, py313-django{42,52}

[gh-actions]
python =
    3.12: py312
    3.13: py313

[testenv]
...

When using pre-release versions of Python, please do not specify -beta or -dev in tox.ini.

.github/workflows/<workflow>.yml:

...
jobs:
  build:
    strategy:
      matrix:
        python-version: [3.14, 3.15.0-beta.3]
...

tox.ini:

[tox]
envlist = py39, py310

[gh-actions]
python =
    3.14: py314
    3.15: py315
    # The following won't work
    # 3.15-beta.3: py315
    # 3.15-dev: py315

[testenv]
...

Added in 3.5.0: To use a free-threaded Python build, add the t suffix.

tox.ini:

[tox]
envlist = py314, py314t

[gh-actions]
python =
    3.14: py314
    3.14t: py314t

[testenv]
...

PyPy is also supported in the python configuration key. Support of Pyston is experimental and not tested by our CI.

tox.ini:

[tox]
envlist = py313, py314, pypy3, pyston38

[gh-actions]
python =
    3.13: py313
    3.14: py314, mypy
    pypy-3.11: pypy3
    pyston-3.8: pyston38

[testenv]
...

[testenv:pyston38]
basepython = pyston38

You can also specify without minor versions in the python configuration key.

tox.ini:

[tox]
envlist = py3, pypy3

[gh-actions]
python =
    3: py3, mypy
    pypy-3: pypy3

[testenv]
...

If there are multiple matching Python versions in the configuration, only the most precise one is used. For example, if you are running CPython 3.14 and gh-actions.python has both 3 and 3.14, tox-gh-actions gets factors only from the key 3.14.

Changed in 3.0: pypy3 is not supported in the configuration anymore. Please use pypy-3 instead.

You can also use environment variable to decide which environment to run. The following is an example to install different dependency based on platform. It will create 9 jobs when running the workflow on GitHub Actions.

• On Python 3.10/ubuntu-latest job, tox runs py310-linux environment
• On Python 3.12/ubuntu-latest job, tox runs py312-linux environment
• and so on.

.github/workflows/<workflow>.yml:

name: Python package

on:
  - push
  - pull_request

jobs:
  build:
    runs-on: ${{ matrix.platform }}
    strategy:
      matrix:
        platform: [ubuntu-latest, macos-latest, windows-latest]
        python-version: ['3.10', '3.12', '3.14']

    steps:
    - uses: actions/checkout@v5
    - name: Set up Python ${{ matrix.python-version }}
      uses: actions/setup-python@v6
      with:
        python-version: ${{ matrix.python-version }}
    - name: Install dependencies
      run: |
        python -m pip install --upgrade pip
        python -m pip install tox tox-gh-actions
    - name: Test with tox
      run: tox
      env:
        PLATFORM: ${{ matrix.platform }}

tox.ini:

[tox]
envlist = py{310,312,314}-{linux,macos,windows}

[gh-actions]
python =
    3.10: py310
    3.12: py312
    3.14: py3114

[gh-actions:env]
PLATFORM =
    ubuntu-latest: linux
    macos-latest: macos
    windows-latest: windows

[testenv]
deps =
  <common dependency>
  linux: <Linux specific deps>
  macos: <macOS specific deps>
  windows: <Windows specific deps>
...

Changed in 3.0: Environment variables should not use lowercase letters. Because of the limitation in tox's configuration loading API, tox-gh-actions always convert keys in [gh-actions:env] to uppercase.

If your project uses tox's requires configuration, you must add tox-gh-actions to the requires configuration as well. Otherwise, tox-gh-actions won't be loaded as a tox plugin.

[tox]
requires =
  tox-conda
  tox-gh-actions

Changed in 2.0: When a list of environments to run is specified explicitly via -e option or TOXENV environment variable (tox's help), tox-gh-actions respects the given environments and simply runs the given environments without enforcing its configuration.

Before 2.0, tox-gh-actions was always enforcing its configuration even when a list of environments is given explicitly.

This project follows PEP 440 and uses a format of major.minor.patch (X.Y.Z). The major version (X) will be incremented when we make backward incompatible changes to a public API. The public API of this project is the configuration of tox-gh-actions. The major version can be also incremented when we require a new version of tox.

This project tries not to introduce backward incompatibles changes as much as possible so that users don't need to update their project's configuration too frequently.

tox-gh-actions 3.x may drop support of unsupported Python 3.y versions in the future without bumping its major version.

We recommend to use the latest version of tox 4.x and tox-gh-actions 3.x. To use tox-gh-actions with tox 3.x, please install tox-gh-actions 2.x. The following table shows compatibility between tox and tox-gh-actions.

See ARCHITECTURE.md for more details.

tox-gh-actions writes log messages using the standard logging module. This is handy for understanding behavior of tox-gh-actions and for debugging tox-gh-actions. To see the log messages, please run tox -vv.