Stabilize unknown payload narrowing
Medium TypeScript arena: unknown, type guards, narrowing, and runtime validation boundaries
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Missing prerequisites: typescript-easy-type-narrowing
Webhook payloads arrive as unknown JSON and must be narrowed before use. You are working inside a TypeScript monorepo, and the arena only clears when the result is safe, deterministic, and explainable.
Learn to apply unknown, type guards, narrowing, and runtime validation boundaries in a TypeScript monorepo while explaining the invariant, safety constraints, and hidden edge cases.
- Demonstrates unknown, type guards, narrowing, and runtime validation boundaries
- Handles the visible sample and hidden edge cases
- Keeps output deterministic and explainable
- Avoids unsafe dynamic execution
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Genie Mentor Core
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