Research Engineer, Codex

OpenAI OpenAI · AI Frontier · San Francisco, CA · Research

Research Engineer role focused on building and improving AI systems for code generation, reasoning, and agentic behavior. The role involves research, experimentation, system optimization, and deployment across the full lifecycle of coding capabilities, aiming to enhance products like ChatGPT and the API.

What you'd actually do

  1. Design and run experiments to improve code generation, reasoning, and agentic behavior in Codex models.
  2. Develop research insights into model training, alignment, and evaluation.
  3. Hunt down and address inefficiencies across the Codex system stack—from agent behavior to LLM inference to container orchestration—and land high-leverage performance improvements.
  4. Build tooling to measure, profile, and optimize system performance at scale.
  5. Work across the stack to prototype new capabilities, debug complex issues, and ship improvements to production.

Skills

Required

  • ML research
  • systems engineering
  • performance optimization
  • software engineering skills
  • operating across ML systems and cloud infrastructure

Nice to have

  • deep curiosity
  • strong technical fundamentals
  • bias toward impact
  • creativity and rigor to open-ended research problems
  • thrive in highly iterative, ambiguous environments

What the JD emphasized

  • push the frontier of code generation and agentic reasoning
  • state-of-the-art AI systems
  • agentic behavior

Other signals

  • building state-of-the-art AI systems
  • push the frontier of code generation and agentic reasoning
  • deploy these capabilities in real-world products