Founding Harness Engineer

Founding Harness Engineer - Jared, Hire an A[I] Player SF, in person. No remote. Bay Area or willing to relocate. $250-350k base + equity. Jared is an AI coworker for teams. You'll build the harness that makes it act like a useful teammate: proactive when it should be, careful when an action needs approval, dependable enough for real work. What you'll do: - Design and build the agent runtime: how Jared gets context, decides when to speak, chooses tools, waits for approval, completes work - Write and iterate system prompts: proactive without noisy or reckless - Build eval and regression tests around real tasks, tool use, failure cases. Prompt changes are code: test them, catch regressions - Make behavior reliable across long-running work, interruptions, retries - Build safe boundaries: approval gates, multi-tenant data separation - Work directly with the founder and early users What we're looking for: - Shipped agents that use tools in production, not demos or prompt wrappers - Knows how to get an agent to take useful initiative, and when it should act, ask, or stay quiet - Hands-on system prompt design improved through testing - Strong regression/eval harness experience - Understands safe tool execution, approval gates, multi-user data risk - Owns broad problems prototype to production, explains tradeoffs - Wants a founding role, in person in SF To apply: share a concrete agent system you built and shipped - a production prompt or safe excerpt, how you evaluated it, one real failure, and what you changed. No confidential info. Process: short async video screen first, reviewed by us, not auto-scored.