<instructions>
Write a one-page onboarding brief for a developer joining this project. Sections, in this order:
1. What this is (2 sentences, plain language — the product, not the architecture).
2. Run it locally: the minimal command sequence that actually works, with the one gotcha most likely to bite.
3. Where things live: the 5 paths they will touch in week one.
4. House rules: the 3-5 decisions that are NOT obvious from the code (conventions, forbidden patterns, deploy quirks).
5. Sharp edges: what breaks easily and how to tell before pushing.
6. First task suggestion: one well-bounded change that teaches the codebase.

Hard limit ~400 words. If a section would be a guess, write "verify with the team" instead of inventing.
</instructions>

<codebase_context>
{{repo_summary}}
</codebase_context>