headroom/CONTRIBUTING.md

# Contributing to Headroom

Thanks for contributing! Please skim this before opening a PR : the policies exist because we've been burned skipping them, not because we love paperwork.

By participating, you agree to our [Code of Conduct](CODE_OF_CONDUCT.md).

## Where does my contribution go?

| Type | What to do |
| --- | --- |
| 🐛 Bug or small fix | **Open a PR** (with repro + test) |
| ✨ New feature / architectural change | **Open an issue or ask in Discord first.** |
| 🧹 Refactor-only | **Don't.** Only if a maintainer asked, as part of a concrete fix. |
| 🧪 Test/CI-only PR chasing a known `main` failure | **Don't.** We're tracking it. |
| 📦 New dep or version bump | **PR with written justification.** |
| ❓ Question | Ask in **Discord `#help`** |

**Open PR cap: 10 per author.** Get existing ones merged before opening more.

## Guiding principles

- **Verification is the author's job, not the reviewer's.**
- **Supply chain is a real threat.** Dependency changes get human review, every time.

## Bug fixes

Every bug-fix PR must include:

1. **A reproduction** — minimal code, failing test, or steps.
2. **A test that fails before your fix and passes after** (unit, integration, or e2e).

If you genuinely can't write a test, say so explicitly and explain how you verified.

## "Real behavior proof" — required on every external PR

We can't merge what we can't verify. Include a **`Real behavior proof`** section in the PR body covering:

- **Setup you tested on** (OS, Python, config, provider/model)
- **Exact command or steps you ran after the patch**
- **After-fix evidence** + **observed result**
- **What you did *not* test**

✅ Counts: screenshots, recordings, terminal output, copied live output, linked artifacts, redacted runtime logs.
❌ Does **not** count alone: unit tests, mocks, snapshots, lint, typechecks, green CI. Have them too — but they prove the test passes, not that the feature works.

**PRs missing this may be autoclosed.**

## New features

Before writing code:

1. **Open a feature-request issue** (or raise in Discord).
2. **Get a 👍 from a core maintainer** before implementing.
3. **Include a short spec** covering:
   - **API surface** (public functions, config, CLI flags)
   - **Changes to existing behavior**
   - **User stories** — Given / When / Then, golden path + one edge case
   - **Failure modes**
   - **Recovery / resilience**
   - **Security considerations**

Short and concrete beats long.

## Dependencies & supply chain

A human maintainer reviews every dep change. PRs that add or bump a package must justify:

- **Why this package** (vs. doing it ourselves / using existing deps)
- **Who maintains it** (activity, release cadence, security history)
- **Install surface** (transitive deps, native code, install/runtime network)
- **Why this version** — permitted reasons: **bug fix**, **security patch**, **required new functionality**. Cosmetic bumps will be closed.

## PR workflow

1. Fork, branch from `main`.
2. Install **Node 18+** and run `uv sync --extra dev` then `make install-git-hooks` — installs repo pre-commit checks on every commit, commitlint on every commit message, and ci-precheck on every push.
3. One logical change per PR.
4. Add tests.
5. `uv run pytest` · `uv run ruff check .` · `uv run ruff format .`
6. Do **not** edit `CHANGELOG.md` — release-please generates it from your Conventional Commit PR title, so a clear `fix(...)`/`feat(...)` title *is* your changelog entry. A CI guard rejects manual edits.
7. Open the PR with a clear description + `Real behavior proof` + any spec/justification required, and keep the PR in draft until the `Review Readiness` boxes are complete.

**Title format** (conventional commits): `feat:`, `fix:`, `docs:`, `test:`, `refactor:`.

**Commit message format** is enforced locally by the repo's `commit-msg` hook and again in CI.

**Review:** CI green, one maintainer review, coverage held/improved.

## Development setup

```bash
git clone https://github.com/chopratejas/headroom.git
cd headroom
python -m venv .venv && source .venv/bin/activate
node --version  # Node 18+ required for commitlint hooks
python -m pip install --upgrade pip
python -m pip install -e ".[dev,relevance,proxy]"
python -m pytest
```

Headroom uses a `pyproject.toml`/`maturin` build backend. Older `pip`
versions may fail editable installs by looking for `setup.py`; upgrade `pip`
first or use `uv sync --extra dev`.

### Dev Containers

Two configs ship for VS Code / Codespaces:

- **`.devcontainer/devcontainer.json`** — Python 3.12, `uv`, Node.js, `gh`.
- **`.devcontainer/memory-stack/devcontainer.json`** — adds Qdrant + Neo4j sidecars (use `qdrant:6333`, `neo4j://neo4j:7687`).

Inside, use: `uv run ruff check .`, `uv run pytest`, etc.

## Optional automated review

This repository includes `.github/copilot-instructions.md` so maintainers can opt into GitHub Copilot code review without adding workflow billing noise to every PR.

Enable or disable automatic Copilot review in **Settings → Rules → Rulesets → Automatically request Copilot code review**. Keep it off unless maintainers explicitly want the extra review traffic.

## Coding standards

- [Ruff](https://github.com/astral-sh/ruff) for lint + format, line length 100, PEP 8.
- Type hints on public functions; Google-style docstrings.
- Cover new behavior + edge cases; aim >80% coverage on new code.
- Python 3.10+. Optional features go behind extras.

## Architecture principles

**Safety first:** never drop user/assistant content, never break tool call/response pairing, malformed content passes through unchanged, prefer false negatives.

**Performance:** transforms <50ms at P99, lazy-load optional deps, profile before optimizing.

Contributors are credited in `CHANGELOG`, the GitHub contributors page, and release notes. Thanks again. 💚