Software Engineer, Codex App
OpenAI
London, United Kingdom
Onsite
mid-level
June 12, 2026
€227,500
€83,202
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Job Description
About The Team The Codex App team owns the desktop application and IDE extension that bring Codex into developers’ daily workflows. We build product experiences end-to-end, and we care equally about usability, performance, and reliability.
Our stack is centered on a TypeScript/Node/Electron application that interfaces with external systems including the Codex CLI and app server (Rust). Building great features here often means designing clean boundaries between UI, local services, and native processes — and making the whole system observable and resilient.
About The Role We’re hiring a Full Stack Software Engineer to build and evolve the systems that power the Codex desktop app and IDE extension. “Full stack” here means owning flows from UI → Node/TypeScript backend layers → IPC/process orchestration → integration with Rust services.
This is a product-minded role. You’ll help define workflows, pick the right abstractions, and ship features that feel fast and dependable in real developer environments.
What You’ll Do
- Build end-to-end features across the Electron app (UI + Node/TypeScript backend layers).
- Design robust integrations with the Codex CLI and app server (Rust), including process lifecycle, streaming output, and error handling.
- Own IPC architecture and patterns (renderer/main boundaries, message schemas, backpressure, safety, debugging).
- Build systems for orchestration: long-running tasks, incremental progress updates, cancellation, retries, and state synchronization.
- Improve reliability, observability, and performance (logging/tracing/metrics, profiling, crash/debug tooling).
- Partner with design and product to turn ambiguous needs into crisp, shippable workflows.
You Might Thrive Here If You
- Have strong TypeScript/Node fundamentals and enjoy owning product features end-to-end.
- Have experience with Electron or desktop app architecture (renderer/main separation, performance pitfalls, packaging/release concerns).
- Are comfortable integrating with native processes/services (e.g., Rust) and designing clean, testable boundaries.
- Know (or are excited to learn) IPC patterns and distributed-systems-like thinking applied locally: message ordering, buffering, backpressure, retries, idempotency.
- Bring strong product judgment and enjoy iterating based on real usage and feedback.
- Have experience with developer tools, CLIs, or IDE integrations (nice-to-have).
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, color, national origin, sex, sexual orientation, age, veteran status, disability, genetic information, or other applicable legally protected characteristic.
For additional information, please see OpenAI’s Affirmative Action and Equal Employment Opportunity Policy Statement.
Background checks for applicants will be administered in accordance with applicable law, and qualified applicants with arrest or conviction records will be considered for employment consistent with those laws, including the San Francisco Fair Chance Ordinance, the Los Angeles County Fair Chance Ordinance for Employers, and the California Fair Chance Act, for US-based candidates. For unincorporated Los Angeles County workers: we reasonably believe that criminal history may have a direct, adverse and negative relationship with the following job duties, potentially resulting in the withdrawal of a conditional offer of employment: protect computer hardware entrusted to you from theft, loss or damage; return all computer hardware in your possession (including the data contained therein) upon termination of employment or end of assignment; and maintain the confidentiality of proprietary, confidential, and non-public information. In addition, job duties require access to secure and protected information technology systems and related data security obligations.
To notify OpenAI that you believe this job posting is non-compliant, please submit a report through this form. No response will be provided to inquiries unrelated to job posting compliance.
We are committed to providing reasonable accommodations to applicants with disabilities, and requests can be made via this link.
OpenAI Global Applicant Privacy Policy
At OpenAI, we believe artificial intelligence has the potential to help people solve immense global challenges, and we want the upside of AI to be widely shared. Join us in shaping the future of technology.
Compensation Range: $230K - $385K
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