Performance & Systems Engineer, Codex
About the Team The Codex team is responsible for building state-of-the-art AI systems that can write code, reason about software, and act as intelligent agents for developers and non-developers alike. Our mission is to push the frontier of code generation and agentic reasoning, and deploy these capabilities in real-wor
What this role actually needs.
About the Team The Codex team is responsible for building state-of-the-art AI systems that can write code, reason about software, and act as intelligent agents for developers and non-developers alike. Our mission is to push the frontier of code generation and agentic reasoning, and deploy these capabilities in real-wor Responsibilities: - Hunt down and address inefficiencies across the Codex system stack, from agent behavior to LLM inference to container orchestration, and beyond. - Build tooling to measure, profile, and optimize system performance at scale. - Collaborate with researchers and engineers to land high-ROI changes that improve latency and cost. - Have experience operating across both ML systems and cloud infrastructure. - Enjoy diving into messy, ambiguous problems and emerging with clear wins. - Think holistically about performance, balancing speed, cost, and user experience. Company context: OpenAI builds frontier AI systems, research infrastructure, and applied products for developers, enterprises, and global users.
Day-to-day expectations
OpenAI lists these responsibilities for the Performance & Systems Engineer, Codex role.
- Hunt down and address inefficiencies across the Codex system stack, from agent behavior to LLM inference to container orchestration, and beyond.
- Build tooling to measure, profile, and optimize system performance at scale.
- Collaborate with researchers and engineers to land high-ROI changes that improve latency and cost.
- Have experience operating across both ML systems and cloud infrastructure.
- Enjoy diving into messy, ambiguous problems and emerging with clear wins.
- Think holistically about performance, balancing speed, cost, and user experience.
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Source: jobs.ashbyhq.com · Source ID: 8a9d680c-5122-4ffe-ab4b-e1de7e806500 · Confidence: 97/100 · Last checked: May 7, 2026
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