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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-world products such as ChatGPT and the API, as well as in next-generation tools specifically designed for agentic coding. We operate across research, engineering, product, and infrastructure—owning the full lifecycle of experimentation, deployment, and iteration on novel coding capabilities.
Job Responsibility:
Design and run experiments to improve code generation, reasoning, and agentic behavior in Codex models
Develop research insights into model training, alignment, and evaluation
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
Build tooling to measure, profile, and optimize system performance at scale
Work across the stack to prototype new capabilities, debug complex issues, and ship improvements to production
Requirements:
Excited to explore and push the boundaries of large language models, especially in the domain of software reasoning and code generation
Strong software engineering skills and enjoy quickly turning ideas into working prototypes
Think holistically about performance, balancing speed, cost, and user experience
Bring creativity and rigor to open-ended research problems and thrive in highly iterative, ambiguous environments
Have experience operating across both ML systems and cloud infrastructure
What we offer:
Medical, dental, and vision insurance for you and your family, with employer contributions to Health Savings Accounts
Pre-tax accounts for Health FSA, Dependent Care FSA, and commuter expenses (parking and transit)
401(k) retirement plan with employer match
Paid parental leave (up to 24 weeks for birth parents and 20 weeks for non-birthing parents), plus paid medical and caregiver leave (up to 8 weeks)
Paid time off: flexible PTO for exempt employees and up to 15 days annually for non-exempt employees
13+ paid company holidays, and multiple paid coordinated company office closures throughout the year for focus and recharge, plus paid sick or safe time (1 hour per 30 hours worked, or more, as required by applicable state or local law)
Mental health and wellness support
Employer-paid basic life and disability coverage
Annual learning and development stipend to fuel your professional growth
Daily meals in our offices, and meal delivery credits as eligible
Relocation support for eligible employees
Additional taxable fringe benefits, such as charitable donation matching and wellness stipends