6. Core Committer Guide

6.1. Vision and Scope

Core committers, use this section to:

  • Guide your instinct and decisions as a core committer
  • Limit the codebase from growing infinitely

6.1.1. Command-Line Accessible

  • Provides a command-line utility that creates projects from cookiecutters
  • Extremely easy to use without having to think too hard
  • Flexible for more complex use via optional arguments

6.1.2. API Accessible

  • Entirely function-based and stateless (Class-free by intentional design)
  • Usable in pieces for developers of template generation tools

6.1.3. Being Jinja2-specific

  • Sets a standard baseline for project template creators, facilitating reuse
  • Minimizes the learning curve for those who already use Flask or Django
  • Minimizes scope of Cookiecutter codebase

6.1.4. Extensible

Being extendable by people with different ideas for Jinja2-based project template tools.

  • Entirely function-based
  • Aim for statelessness
  • Lets anyone write more opinionated tools

Freedom for Cookiecutter users to build and extend.

  • No officially-maintained cookiecutter templates, only ones by individuals
  • Commercial project-friendly licensing, allowing for private cookiecutters and private Cookiecutter-based tools

6.1.5. Fast and Focused

Cookiecutter is designed to do one thing, and do that one thing very well.

  • Cover the use cases that the core committers need, and as little as possible beyond that :)
  • Generates project templates from the command-line or API, nothing more
  • Minimize internal line of code (LOC) count
  • Ultra-fast project generation for high performance downstream tools

6.1.6. Inclusive

  • Cross-platform and cross-version support are more important than features/functionality
  • Fixing Windows bugs even if it’s a pain, to allow for use by more beginner coders

6.1.7. Stable

  • Aim for 100% test coverage and covering corner cases
  • No pull requests will be accepted that drop test coverage on any platform, including Windows
  • Conservative decisions patterned after CPython’s conservative decisions with stability in mind
  • Stable APIs that tool builders can rely on
  • New features require a +1 from 3 core committers

6.1.8. VCS-Hosted Templates

Cookiecutter project templates are intentionally hosted VCS repos as-is.

  • They are easily forkable
  • It’s easy for users to browse forks and files
  • They are searchable via standard Github/Bitbucket/other search interface
  • Minimizes the need for packaging-related cruft files
  • Easy to create a public project template and host it for free
  • Easy to collaborate

6.2. Process: Pull Requests

If a pull request is untriaged:

  • Look at the roadmap
  • Set it for the milestone where it makes the most sense
  • Add it to the roadmap

How to prioritize pull requests, from most to least important:

  1. Fixes for broken tests. Broken means broken on any supported platform or Python version.
  2. Extra tests to cover corner cases.
  3. Minor edits to docs.
  4. Bug fixes.
  5. Major edits to docs.
  6. Features.

Ensure that each pull request meets all requirements in this checklist: https://gist.github.com/audreyr/4feef90445b9680475f2

6.3. Process: Issues

If an issue is a bug that needs an urgent fix, mark it for the next patch release. Then either fix it or mark as please-help.

For other issues: encourage friendly discussion, moderate debate, offer your thoughts.

New features require a +1 from 2 other core committers (besides yourself).

6.4. Process: Roadmap

The roadmap is https://github.com/audreyr/cookiecutter/milestones?direction=desc&sort=due_date&state=open

Due dates are flexible. Core committers can change them as needed. Note that GitHub sort on them is buggy.

How to number milestones:

Milestone size:

  • If a milestone contains too much, move some to the next milestone.
  • Err on the side of more frequent patch releases.

6.5. Process: Pull Request merging and HISTORY.rst maintenance

If you merge a pull request, you’re responsible for updating AUTHORS.rst and HISTORY.rst

When you’re processing the first change after a release, create boilerplate following the existing pattern:

x.y.z (Development)

The goals of this release are TODO: release summary of features


* Feature description, thanks to @contributor (#PR).

Bug Fixes:

* Bug fix description, thanks to @contributor (#PR).

Other changes:

* Description of the change, thanks to @contributor (#PR).

.. _`@contributor`: https://github.com/contributor

6.6. Process: Accepting Template Pull Requests

  1. Run the template to generate the project.
  2. Attempt to start/use the rendered project.
  3. Merge the template in.
  4. Update the history file.


Adding a template doesn’t give authors credit.

6.7. Process: Generating CONTRIBUTING.rst

From the cookiecutter project root:

$ make contributing

This will generate the following message:

cat docs/contributing.rst >> CONTRIBUTING.rst
echo "\n\n" >> CONTRIBUTING.rst
cat docs/types_of_contributions.rst >> CONTRIBUTING.rst
echo "\n\n" >> CONTRIBUTING.rst
cat docs/contributor_setup.rst >> CONTRIBUTING.rst
echo "\n\n" >> CONTRIBUTING.rst
cat docs/contributor_guidelines.rst >> CONTRIBUTING.rst
echo "\n\n" >> CONTRIBUTING.rst
cat docs/contributor_testing.rst >> CONTRIBUTING.rst
echo "\n\n" >> CONTRIBUTING.rst
cat docs/core_committer_guide.rst >> CONTRIBUTING.rst
echo "\n\nAutogenerated from the docs via \`make contributing\`" >> CONTRIBUTING.rst
echo "WARNING: Don't forget to replace any :ref: statements with literal names"
WARNING: Don't forget to replace any :ref: statements with literal names

6.8. Process: Your own code changes

All code changes, regardless of who does them, need to be reviewed and merged by someone else. This rule applies to all the core committers.


  • Minor corrections and fixes to pull requests submitted by others.
  • While making a formal release, the release manager can make necessary, appropriate changes.
  • Small documentation changes that reinforce existing subject matter. Most commonly being, but not limited to spelling and grammar corrections.

6.9. Responsibilities

  1. Ensure cross-platform compatibility for every change that’s accepted. Windows, Mac, Debian & Ubuntu Linux.
  2. Ensure that code that goes into core meets all requirements in this checklist: https://gist.github.com/audreyr/4feef90445b9680475f2
  3. Create issues for any major changes and enhancements that you wish to make. Discuss things transparently and get community feedback.
  4. Don’t add any classes to the codebase unless absolutely needed. Err on the side of using functions.
  5. Keep feature versions as small as possible, preferably one new feature per version.
  6. Be welcoming to newcomers and encourage diverse new contributors from all backgrounds. See the Python Community Code of Conduct (https://www.python.org/psf/codeofconduct/).

6.10. Becoming a Core Committer

Contributors may be given core commit privileges. Preference will be given to those with:

  1. Past contributions to Cookiecutter and other open-source projects. Contributions to Cookiecutter include both code (both accepted and pending) and friendly participation in the issue tracker. Quantity and quality are considered.
  2. A coding style that the other core committers find simple, minimal, and clean.
  3. Access to resources for cross-platform development and testing.
  4. Time to devote to the project regularly.