How to contribute

ComfyUI is an open-source GPL-3.0 project. Contributions go through GitHub pull requests against master. This section covers the practical mechanics of working in this codebase.

Where to start

• For bugs and feature requests: open an issue.
• For questions: prefer the Discord or Matrix space — see CONTRIBUTING.md.
• For frontend bugs: file in Comfy-Org/ComfyUI_frontend, not here.

Pull requests

CONTRIBUTING.md points at the wiki page "How to Contribute Code" for the canonical PR walkthrough. Beyond what's there, this codebase has a few specific habits to keep in mind:

• Keep changes additive when possible. The codebase has heavy custom-node use; subtle changes to executor behavior, model-management heuristics, or comfy_api/ types ripple outward.
• Don't reorder imports in comfy/sd.py, nodes.py, or main.py casually. These files have load-order constraints (e.g., torch must not be imported before main.py configures device env vars).
• Mirror existing patterns. New model architectures follow the template of the most recent additions: a folder under comfy/ldm/<model>/, an entry in comfy/supported_models.py, encoder code under comfy/text_encoders/, and nodes in comfy_extras/nodes_<model>.py.

Code review expectations

CI runs ruff check, the unit test suite, an execution test, a quick launch smoke test, and a build test on every PR. See Tooling. All four must pass before merge.

The repository has a CI hook that flags AI-co-authored commits (.github/workflows/check-ai-co-authors.yml) and a line-endings check.

Definition of done

Before opening a PR:

1. ruff check . passes.
2. pytest tests-unit passes.
3. Manual smoke: python main.py --quick-test-for-ci exits cleanly.
4. If you touched a model: run a relevant workflow and confirm output sanity.
5. If you touched the executor or caching: run pytest tests/execution (this hits a running server).

What's in this section

• Development workflow — branch, code, test, PR
• Testing — unit and integration tests
• Debugging — logs, common errors
• Patterns and conventions — how the team writes code in this repo
• Tooling — lint, CI, build, release