About the job
We are looking for a backend software engineer to build and operate the services behind the Responses API. You will shape API behavior, bring new capabilities from research into production, and make long-running agent workflows dependable and fast. The work combines distributed systems engineering with product judgment: designing useful developer interfaces, managing staged rollouts, and following production issues through to durable fixes.
Responsibilities
- Design, build, and operate APIs and backend services that bring frontier model capabilities to developers.
- Partner with Research, Safety, Codex, and API teams to define API behavior and deliver safe, staged launches.
- Build API capabilities for agent workflows, including task delegation, context sharing, and parallel execution.
- Strengthen long-running request reliability across timeouts, cancellation, streaming, and background execution.
- Improve request-processing performance and tail latency through profiling, efficient systems code, and persistent connections.
- Turn developer feedback and production failures into better observability, diagnostics, and lasting product improvements.
Qualifications
Minimum
- 5+ years of experience building and operating backend services or developer-facing APIs in production.
- Strong software engineering fundamentals, with practical knowledge of distributed systems, concurrency, and asynchronous execution.
- Ability to diagnose production failures and performance bottlenecks using observability data and profiling.
- Product judgment and developer empathy, with a track record of translating complex capabilities into clear, dependable APIs.
- Experience taking ownership of ambiguous technical problems, from defining an approach through shipping and improving the result.
- Clear communication and effective collaboration across engineering, research, product, and safety disciplines.
Preferred
- Experience with Rust, streaming protocols or WebSockets, or long-running workflow systems is a plus.