Optimize Object-Backed APIs and Design an LLM Observability Platform
Company: Langchain
Role: Software Engineer
Category: System Design
Difficulty: medium
Interview Round: Onsite
Overview: A two-part system-design interview about reducing latency in object-backed JSON APIs and building an LLM observability platform. It emphasizes measurement-driven optimization, trace ingestion, tagged metrics, exact token billing, durable alerts, and anomaly evaluation.
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