Staff Software Engineer, AI Developer Experience

Thesis • New York, NY

9h • $225,000 - $275,000 • Hybrid

About The Position

Thesis is seeking a Staff Software Engineer specializing in AI Developer Experience to develop the core systems that enable the entire company to ship products. As product managers, designers, and operators increasingly leverage AI, the goal is to maintain the rigor, security, and maintainability essential for a healthcare business. This foundational role involves designing and building a 'paved road' infrastructure, including a typed API framework, tenant-safe data access layer, migration tooling, and progressive delivery infrastructure. The engineer will establish patterns for code development for years to come, collaborating with engineering leadership on structural enforcement, human review processes, and runtime monitoring, and serving as a key resource for product managers.

Requirements

• Staff-level engineering experience: 8+ years building production systems, with significant time spent on platform, infrastructure, or developer-experience work, having set lasting patterns at previous companies.
• Deep TypeScript and Postgres fluency: Ability to read and write advanced TypeScript types and understand Postgres concepts like indexes, locks, query plans, and live table migrations. Direct experience with Drizzle, Kysely, or similar typed query builders is a strong plus.
• A safety-through-types instinct: Preference for using the type system and framework to enforce correctness, aiming for abstractions where 'the wrong thing doesn’t compile'.
• Security literacy: Understanding of multi-tenant isolation, common web application vulnerabilities, defense in depth, and experience with or eagerness to set up CI security tooling (SAST, secrets scanning, dependency auditing).
• Empathy for non-engineer users: Ability to design user-friendly API surfaces for product managers and genuine interest in creating tools that are adopted rather than bypassed.
• AI fluency: Experience building with modern AI coding tools, with a considered view on their benefits, pitfalls, and necessary guardrails for AI-generated code at scale.
• Healthcare awareness: Experience building systems with sensitive data in regulated environments, or a strong interest in learning healthcare workflows and constraints.
• Clear communication: Ability to explain complex technical concepts clearly to both technical and non-technical stakeholders.
• NYC-based: Must be based in New York and willing to be in-office approximately 3 days per week.

Nice To Haves

• Experience designing API frameworks (tRPC, typed REST, GraphQL) where conventions are enforced by the framework itself, not by review.
• Experience running progressive delivery systems (LaunchDarkly, Statsig, or homegrown).
• Experience in a company that successfully enabled non-engineers to ship production code—or a company that tried and failed, with understanding of why.
• Experience with Postgres row-level security in production.

Responsibilities

• Design and build the platform primitives, including the data access layer (TypeScript + Drizzle + Postgres), endpoint framework, feature flag integration, progressive delivery tooling, migration scaffolding, and KV/events primitives, owning both architecture and code.
• Encode conventions into the type system, CI, and runtime (e.g., TypeScript signatures, lint rules, Semgrep checks, runtime assertions) to ensure system enforceability over human memory.
• Enable non-engineer builders by designing scaffolders, documentation, and agent-style guides that allow product managers with AI assistance to ship well-formed features quickly.
• Partner with the engineering team on reviews and unblocking, running the schema review process, extending the data layer for new patterns, shaping CODEOWNERS structure, and coaching engineers on 'PM enablement' duty.
• Own governance rituals such as weekly platform review, monthly architecture review, and quarterly cleanup, monitoring for drift and duplication, and removing unnecessary components.
• Handle production incidents on the platform, identifying and fixing the root cause of bugs in shared infrastructure rather than just individual instances.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior
• Education Level: No Education Listed