Senior Member of Technical Staff, Harness Engineering

Harper is a company focused on building AI-led commercial insurance distribution, aiming to improve coverage for businesses. They are seeking a Senior Member of Technical Staff to develop the harness layer that supports their product and coding agents, ensuring efficient delivery of agent functionalities.

Responsibilities:

• Build agent loop primitives - Prompt construction, tool routing, retry/timeout/budget logic, multi-step orchestration
• Ship execution-environment infra - Sandbox lifecycle, isolation, blast-radius limits, filesystem + network policy for agents
• Own the tool layer for assigned domains - Schema, auth, rate-limit, observability per tool. Tools other engineers consume
• Wire model-provider routing - Provider fallback chains, eval-driven model selection, cost/latency tradeoffs
• Ship harness SDK improvements - Whatever makes pod engineers faster
• Eat your own dog food - You write code with our harness daily and feel every rough edge