Development Guide

Some general guidelines regarding development in pytest for core maintainers and general contributors. Nothing here is set in stone and can’t be changed, feel free to suggest improvements or changes in the workflow.

Code Style


We have two long term branches:

  • master: contains the code for the next bugfix release.
  • features: contains the code with new features for the next minor release.

The official repository usually does not contain topic branches, developers and contributors should create topic branches in their own forks.

Exceptions can be made for cases where more than one contributor is working on the same topic or where it makes sense to use some automatic capability of the main repository, such as automatic docs from readthedocs for a branch dealing with documentation refactoring.


Any question, feature, bug or proposal is welcome as an issue. Users are encouraged to use them whenever they need.

GitHub issues should use labels to categorize them. Labels should be created sporadically, to fill a niche; we should avoid creating labels just for the sake of creating them.

Here is a list of labels and a brief description mentioning their intent.


  • type: backward compatibility: issue that will cause problems with old pytest versions.
  • type: bug: problem that needs to be addressed.
  • type: deprecation: feature that will be deprecated in the future.
  • type: docs: documentation missing or needing clarification.
  • type: enhancement: new feature or API change, should be merged into features.
  • type: feature-branch: new feature or API change, should be merged into features.
  • type: infrastructure: improvement to development/releases/CI structure.
  • type: performance: performance or memory problem/improvement.
  • type: proposal: proposal for a new feature, often to gather opinions or design the API around the new feature.
  • type: question: question regarding usage, installation, internals or how to test something.
  • type: refactoring: internal improvements to the code.
  • type: regression: indicates a problem that was introduced in a release which was working previously.


  • status: critical: grave problem or usability issue that affects lots of users.
  • status: easy: easy issue that is friendly to new contributors.
  • status: help wanted: core developers need help from experts on this topic.
  • status: needs information: reporter needs to provide more information; can be closed after 2 or more weeks of inactivity.


  • topic: collection
  • topic: fixtures
  • topic: parametrize
  • topic: reporting
  • topic: selection
  • topic: tracebacks

Plugin (internal or external)

  • plugin: cache
  • plugin: capture
  • plugin: doctests
  • plugin: junitxml
  • plugin: monkeypatch
  • plugin: nose
  • plugin: pastebin
  • plugin: pytester
  • plugin: tmpdir
  • plugin: unittest
  • plugin: warnings
  • plugin: xdist


Issues specific to a single operating system. Do not use as a means to indicate where an issue originated from, only for problems that happen only in that system.

  • os: linux
  • os: mac
  • os: windows


Used to classify issues for limited time, to help find issues related in events for example. They should be removed after they are no longer relevant.

  • temporary: EP2017 sprint:
  • temporary: sprint-candidate:

Release Procedure

Our current policy for releasing is to aim for a bugfix every few weeks and a minor release every 2-3 months. The idea is to get fixes and new features out instead of trying to cram a ton of features into a release and by consequence taking a lot of time to make a new one.


pytest releases must be prepared on Linux because the docs and examples expect to be executed in that platform.

  1. Install development dependencies in a virtual environment with:

    pip3 install -r tasks/requirements.txt
  2. Create a branch release-X.Y.Z with the version for the release.

    • patch releases: from the latest master;
    • minor releases: from the latest features; then merge with the latest master;

    Ensure your are in a clean work tree.

  3. Generate docs, changelog, announcements and upload a package to your devpi staging server:

    invoke generate.pre-release <VERSION> <DEVPI USER> --password <DEVPI PASSWORD>

    If --password is not given, it is assumed the user is already logged in devpi. If you don’t have an account, please ask for one.

  4. Open a PR for this branch targeting master.

  5. Test the package

    • Manual method

      Run from multiple machines:

      devpi use
      devpi test pytest==VERSION

      Check that tests pass for relevant combinations with:

      devpi list pytest
    • CI servers

      Configure a repository as per-instructions on devpi-cloud-test to test the package on Travis and AppVeyor. All test environments should pass.

  6. Publish to PyPI:

    invoke generate.publish-release <VERSION> <DEVPI USER> <PYPI_NAME>

    where PYPI_NAME is the name of as configured in your ~/.pypirc file for devpi.

  7. After a minor/major release, merge release-X.Y.Z into master and push (or open a PR).