Implement idempotent request handling with idempotency keys
Company: Microsoft
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: hard
Interview Round: Onsite
Overview: This question evaluates understanding of idempotency semantics, idempotency-key handling, concurrency control, synchronization, and in-memory TTL-based caching for API request processing, and it belongs to the Coding & Algorithms domain with an emphasis on practical application.