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+# Contributing to nullTickets
+
+1. **Read [AGENTS.md](AGENTS.md)** first — it defines the engineering protocol,
+   module map, and conventions for this repository.
+2. One concern per PR. No drive-by refactors.
+3. Before every commit:
+   - `zig build test --summary all` — 0 failures, 0 leaks
+   - `bash tests/test_e2e.sh` — end-to-end API flow must pass
+   - `zig fmt --check src/`
+4. Every PR runs unit tests on Linux, macOS and Windows, plus Linux
+   aarch64/riscv64 cross-compilation. Keep it green.
+5. Bug fixes must include a regression test citing the issue number.
+6. REST API changes must keep `/openapi.json` and `/.well-known/openapi.json`
+   exports in sync — the tracker contract is consumed by agents and
+   orchestrators that depend on it.