Senior Member of Technical Staff

About the Company

Harper is an AI-native commercial insurance company in San Francisco. We're rebuilding the entire business as software, turning expert human judgment into compute. We move at high speed with very high standards.

Responsibilities

• Build agent-loop primitives including prompt construction, tool routing, and multi-step orchestration
• Ship execution-environment infrastructure such as sandbox lifecycle and isolation
• Own the tool layer including schema, auth, rate-limiting, and observability
• Wire model-provider routing and provider fallback chains
• Ship harness SDK improvements to increase engineer velocity
• Use the internal harness daily to write code and identify improvements

Requirements

• 3–6 years of software engineering experience
• Experience building production agentic systems with real users and traffic
• Experience with at least one major agent framework
• Proficiency in tool design and sandbox decision-making
• Experience with production agent/LLM systems, agent loops, and prompt engineering at scale
• Ability to manage multiple parallel AI coding sessions daily
• Strong written communication for API contracts and documentation

Preferred Qualifications

• Experience with sandbox or isolation infrastructure
• Open-source agent-framework contributions
• Foundation-model partner or early-access experience

Benefits

• Compensation: $187,000–$264,000 cash (base + target performance bonus) plus competitive equity
• Uber commuter benefits
• Breakfast, lunch, and dinner provided
• Snacks and coffee stocked
• Free gym membership
• Health, dental, and vision insurance