Software Engineer, Codex Core Agents
Builds infrastructure for AI agents in production, focusing on sandboxed code execution, orchestration, stateful workflows, and optimization for tokens, latency, reliability, and cost at scale. Requires strong distributed systems and infrastructure engineering experience.
About the job
What You’ll Do
- Design and build execution environments for AI agents, including sandboxing, isolation, and reproducibility.
- Develop systems for agent orchestration across multi-step, tool-using workflows.
- Build infrastructure for running, testing, and debugging code generated by models.
- Create state and memory systems that allow agents to persist context across long-running tasks.
- Optimize tokens, latency, reliability, and cost across Codex’s production fleet.
- Support model rollouts, capacity planning, and the core tradeoffs between quality, speed, and economics to manage a fleet of frontier agents at scale.
- Build shared platform capabilities that unblock product teams, partner teams, and open source Codex.
What You Might Be a Good Fit If You
- Have strong experience in distributed systems or infrastructure engineering.
- Have built systems involving containers, sandboxing, or virtualization.
- Are comfortable working across backend systems, APIs, and developer tooling.
- Care deeply about system reliability, performance, and security.
- Enjoy working on ambiguous, zero-to-one problems.
- Want to help build the systems that turn model capability into a dependable software engineering agent.
Bonus Points
- Experience with code execution platforms, CI/CD systems, or build systems.
- Familiarity with LLMs, agents, or tool-use frameworks.
- Background in security engineering or isolation systems.
- Experience building developer platforms, IDE tooling, or open source infrastructure.
Skills
Distributed Systems, Containers, Sandboxing, Virtualization, APIs, Developer Tooling, CI/CD, LLMs, Kubernetes, Docker
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