Software Engineer, Codex Runtime

About the Team

With Codex we're building an AI software engineer. One that you can pair with, delegate to, or even ask to take on future tasks proactively. Our team is a fast-moving group within OpenAI, bringing together research, engineering, design, and product. We iteratively build the Codex agent harness and product to get the most out of the model, and we iteratively train the model to be great at complex software engineering tasks.

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. We operate across research, engineering, product, and infrastructure; owning the full lifecycle of experimentation, deployment, and iteration on novel coding capabilities.

Codex for Teams builds products and platform capabilities to drive the adoption of Codex in diverse team environments. It is a cross-cutting team that works across the stack to build both delightful product experiences and fundamental platform capabilities. Its customers range from small teams to large enterprises, and our mission is critical to achieving the vision of Codex as a proactive teammate.

Codex Runtime is the execution and infrastructure layer that turns Codex from a code generator into a real AI software engineer operating  provides secure, sandboxed environments where Codex can run commands, read and write files, execute tests, and iteratively improve its work across real codebases - just like a human developer. More broadly, Codex Runtime is the distributed systems substrate that enables large numbers of supervised AI agents to run inside OpenAI's and customers' data centers, tackling increasingly complex goals over long time horizons.

By giving agents a real working context and reliable execution environment, Codex Runtime makes it possible for Codex to validate its own changes, debug failures, and deliver production-ready results, defining how AI agents safely, reliably, and at scale interact with the world's software.

• Shape the evolution of Codex itself by identifying how teams actually use (and break) AI-powered software engineering, and driving changes across product, infrastructure, and model behavior to make Codex a truly reliable teammate for organizations.

• Build the core team and enterprise primitives that make Codex usable at scale including container orchestration, virtual machine provisioning/configuration, execution sandboxes, shared block storage, RBAC, admin and audit surfaces, usage, rate limits and pricing controls, managed configuration and constraints, and analytics that give teams and operators deep visibility into how Codex is being used.

• Design and own secure, observable, full-stack systems that power Codex across web, IDEs, CLI, and CI/CD, integrating with enterprise identity and governance systems (SSO/SAML/OIDC, SCIM, policy enforcement) and building data-access patterns that are performant, compliant, and trustworthy.

• Lead real-world deployments and launches by working directly with customers and GTM to roll Codex out across teams, using live usage and operational signals to rapidly iterate and turn messy, real-world feedback into scalable product and platform improvements.

• Have strong software engineering fundamentals and experience turning ideas into production‑grade large‑scale distributed systems, thinking holistically about balancing speed, performance, costs, and user experience.

• Have been using AI‑powered/agentic software development tools and are familiar with their strengths/weaknesses.

• Have experience with orchestration of scaled containerization and/or virtualization systems (e.g. Kubernetes, OCI).

• Are proficient in one or more backend languages (e.g. Python, Go, Rust) and concurrency/distributed systems concepts, with a focus on reliability, observability, and security.

• Enjoy building cross‑cutting platform capabilities that unlock product velocity, and you’re comfortable working across services, APIs, and end‑user product surfaces.

• Have experience with team/enterprise foundations such as…