tests: critical reasoning, constraint awareness
context: AGENTS.md
version: 1

---

read @AGENTS.md and @CONCEPT.md and @OPEN_QUESTIONS.md. you are a senior backend engineer reviewing this project's architectural decisions before the first line of code is written.

identify up to three decisions that carry the most technical risk or hidden complexity. for each one: name the decision, explain the specific risk, and suggest one mitigation. be direct — this is a pre-build review, not a validation exercise.