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For Companies At a Glance
- Tasks: Design and build cutting-edge execution environments for AI agents.
- Company: Join OpenAI, a leader in AI research and deployment.
- Benefits: Competitive salary, flexible work options, and opportunities for professional growth.
- Why this job: Be at the forefront of AI technology and make a real-world impact.
- Qualifications: Experience in distributed systems and a passion for system reliability.
- Other info: Dynamic team environment with a commitment to diversity and inclusion.
The predicted salary is between 60000 - 80000 £ per year.
About The Team
The Codex Core Agent team builds the kernel of Codex. We own making the agent better, accelerating research, and making those improvements real in production for our users. That means working across the systems that make Codex actually function as an agent in the real world: the production performance envelope around tokens, latency, reliability, cost, and capacity; the core execution loop and interfaces that turn models into useful behaviour; the shared infrastructure that enables other teams to build on Codex; and the feedback loops that turn real-world usage into better models and better agent behaviour over time.
About The Role
We’re looking for engineers to build the infrastructure that powers Codex agents in production. This role focuses on the systems that let models safely execute code, interact with tools, complete long-running tasks, and operate reliably and efficiently at scale. You’ll design and operate the infrastructure behind sandboxed execution, orchestration, stateful workflows, app-server and SDK boundaries, and model rollouts. You’ll work at the intersection of distributed systems, developer tooling, and AI, building primitives that make Codex faster, safer, more reliable, and easier for the rest of the organisation to build on.
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.
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.
About OpenAI
OpenAI is an AI research and deployment company dedicated to ensuring that general-purpose artificial intelligence benefits all of humanity. We push the boundaries of the capabilities of AI systems and seek to safely deploy them to the world through our products. AI is an extremely powerful tool that must be created with safety and human needs at its core, and to achieve our mission, we must encompass and value the many different perspectives, voices, and experiences that form the full spectrum of humanity. We are an equal opportunity employer, and we do not discriminate on the basis of race, religion, colour, national origin, sex, sexual orientation, age, veteran status, disability, genetic information, or other applicable legally protected characteristic.
We are committed to providing reasonable accommodations to applicants with disabilities, and requests can be made via this link.
Software Engineer, Codex Core Agents employer: OpenAI
Contact Detail:
OpenAI Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Software Engineer, Codex Core Agents
✨Tip Number 1
Network like a pro! Reach out to folks in the industry, attend meetups, and connect with people on LinkedIn. You never know who might have the inside scoop on job openings or can refer you directly.
✨Tip Number 2
Show off your skills! Create a portfolio or GitHub repository showcasing your projects, especially those related to distributed systems or AI. This gives potential employers a taste of what you can do beyond just a CV.
✨Tip Number 3
Prepare for interviews by practising common technical questions and system design scenarios. We recommend doing mock interviews with friends or using platforms that offer coding challenges to sharpen your skills.
✨Tip Number 4
Apply through our website! It’s the best way to ensure your application gets seen. Plus, it shows you’re genuinely interested in being part of our team at StudySmarter.
We think you need these skills to ace Software Engineer, Codex Core Agents
Some tips for your application 🫡
Tailor Your Application: Make sure to customise your CV and cover letter to highlight your experience with distributed systems and infrastructure engineering. We want to see how your skills align with the role of building the infrastructure for Codex agents!
Showcase Relevant Projects: Include any projects or experiences that demonstrate your work with containers, sandboxing, or virtualization. We love seeing real-world examples of how you've tackled similar challenges in the past.
Be Clear and Concise: When writing your application, keep it straightforward and to the point. We appreciate clarity, so make sure your key achievements and skills stand out without unnecessary fluff.
Apply Through Our Website: Don’t forget to submit your application through our website! It’s the best way for us to receive your details and ensure you’re considered for this exciting opportunity with the Codex Core Agent team.
How to prepare for a job interview at OpenAI
✨Know Your Systems
Make sure you brush up on your knowledge of distributed systems and infrastructure engineering. Be ready to discuss your experience with containers, sandboxing, and virtualization, as these are crucial for the role. Prepare examples of how you've tackled similar challenges in the past.
✨Demonstrate Problem-Solving Skills
This role involves working on ambiguous, zero-to-one problems, so be prepared to showcase your problem-solving abilities. Think of a time when you faced a complex issue and explain how you approached it, what solutions you considered, and the outcome.
✨Understand the Tech Stack
Familiarise yourself with the technologies mentioned in the job description, such as CI/CD systems and code execution platforms. If you have experience with LLMs or developer tooling, be ready to discuss how you've used these in your previous roles.
✨Show Passion for Reliability and Security
Since the role focuses on system reliability, performance, and security, express your passion for these areas during the interview. Share any relevant experiences where you prioritised these aspects in your work, and how you ensure that the systems you build are dependable and secure.