Software Engineer, API Frontiers

Details

API Frontiers turns OpenAI’s frontier models into production APIs that developers can use to build reliable products and agents. The team owns the core path connecting models to developers through the Responses API, with a focus on safety, reliability, and speed. It works closely with Research, Safety, Codex, and other API teams to bring new model capabilities into production and improve them through developer feedback.

The role involves building and operating the backend services behind the Responses API, shaping API behavior, bringing new capabilities from research into production, and making long-running agent workflows dependable and fast. The work combines distributed systems engineering with product judgment, including designing developer interfaces, managing staged rollouts, and resolving production issues with 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.

Requirements

• 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.
• Experience with Rust, streaming protocols or WebSockets, or long-running workflow systems is a plus.

Benefits

• Equity, performance-related bonuses for eligible employees, and comprehensive benefits.
• Medical, dental, and vision insurance, with employer contributions to Health Savings Accounts.
• Pre-tax accounts for health, dependent care, and commuter expenses.
• 401(k) retirement plan with employer match.
• Paid parental, medical, and caregiver leave.
• Paid time off, company holidays, office closures, and paid sick or safe time.
• Mental health and wellness support.
• Employer-paid basic life and disability coverage.
• Annual learning and development stipend.
• Daily office meals and eligible meal delivery credits.
• Relocation support for eligible employees.
• Additional taxable fringe benefits may be provided.