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+# Contributing to GroomBook
+
+## Branch Strategy
+
+GroomBook uses a three-branch GitOps model:
+
+| Branch | Environment | Purpose |
+|--------|-------------|---------|
+| `dev` | Development | Active development target — all feature/fix PRs target this branch |
+| `uat` | UAT / Staging | Promoted from `dev` by the CTO for acceptance testing |
+| `main` | Production | Promoted from `uat` by the CEO; triggers production deployment |
+
+**Never open a PR directly to `uat` or `main`.** All work flows through `dev` first.
+
+## Developer Workflow
+
+1. **Branch from `dev`** — create a feature or fix branch:
+   ```bash
+   git checkout dev
+   git pull origin dev
+   git checkout -b feat/my-feature
+   ```
+
+2. **Open a PR targeting `dev`** — include the issue identifier in the title and cc @cpfarhood:
+   ```bash
+   gh pr create --base dev --title "feat: description (GRO-NNN)" \
+     --body $'Closes GRO-NNN\n\ncc @cpfarhood'
+   ```
+
+3. **Pipeline gates before merge to `dev`:**
+   - QA (Lint Roller) reviews first — code quality, test coverage, CI pass
+   - CTO (The Dogfather) reviews second — architecture and final approval
+   - Both must approve; 2 approving reviews required by branch protection
+
+## Promotion Flow
+
+### Dev → UAT
+
+After merging to `dev`, the CTO opens a PR from `dev` → `uat`:
+
+```bash
+gh pr create --base uat --head dev \
+  --title "chore: promote dev to uat (YYYY.MM.DD)" \
+  --body $'Promoting dev to UAT for regression and security review.\n\ncc @cpfarhood'
+```
+
+Gates:
+- Shedward Scissorhands runs regression/acceptance tests
+- Barkley Trimsworth performs security review
+- CTO approves and merges (1 approving review required)
+
+### UAT → Main (Production)
+
+After UAT passes, the CTO opens a PR from `uat` → `main` and assigns it to the CEO:
+
+```bash
+gh pr create --base main --head uat \
+  --title "chore: promote uat to main (YYYY.MM.DD)" \
+  --body $'Promoting UAT to production.\n\ncc @cpfarhood'
+```
+
+Gates:
+- CEO (Scrubs McBarkley) reviews for business alignment and merges
+- 1 approving review required; triggers auto-deploy to Production
+
+## Branch Protection Summary
+
+| Branch | Required Approvals | Who approves |
+|--------|--------------------|-------------|
+| `dev` | 2 | QA (Lint Roller) + CTO (The Dogfather) |
+| `uat` | 1 | CTO (The Dogfather) |
+| `main` | 1 | CEO (Scrubs McBarkley) |
+
+Force-pushes and branch deletions are disabled on all three branches.
+
+## Commit Style
+
+Use [Conventional Commits](https://www.conventionalcommits.org/):
+- `feat:` — new feature
+- `fix:` — bug fix
+- `chore:` — maintenance (dependency updates, build config, promotions)
+- `docs:` — documentation only
+- `ci:` — CI/CD changes
+- `refactor:` — code restructure without behaviour change
+
+Reference the Paperclip issue in the commit body: `Refs GRO-NNN`.
+
+## Questions?
+
+Open a Paperclip issue in the GRO project or ask in the team channel.