Principal Software Engineer, Full Stack — Codex

About the Role We’re hiring a Principal Software Engineer to help define and build the next generation of AI-powered software development workflows. “Full stack” in this role extends well beyond traditional frontend and backend development. You will set technical direction and lead major product initiatives spanning user interfaces, developer tooling, workflow orchestration, agent and prompt design, backend systems, and cloud infrastructure. This is a highly product-oriented technical leadership role. You will identify the highest-leverage opportunities across the software development lifecycle, turn ambiguous user and technical problems into durable product and system strategies, and lead execution across multiple engineers and partner teams. Your work will shape both the architecture of Codex and how developers around the world design, write, review, test, and maintain software. You will operate as a senior individual contributor: remaining deeply involved in design and implementation while raising the technical judgment, execution quality, and ambition of the broader team. In this role, you will Set the technical and product direction for significant areas of Codex, translating an evolving product vision into scalable architectures and an actionable engineering strategy. Lead complex, multi-quarter initiatives spanning client applications, backend services, agent systems, cloud infrastructure, and developer tooling. Design AI-powered workflows that generalize across languages, codebases, development environments, and organizations while remaining intuitive, reliable, and safe. Make high-consequence architectural decisions under ambiguity, balancing rapid product learning with long-term system quality and adaptability. Identify opportunities that cut across existing team or product boundaries, align stakeholders around a direction, and drive the work from exploration through launch and iteration. Partner closely with product, design, research, infrastructure, security, and go-to-market teams to turn emerging model capabilities and developer needs into coherent product experiences. Work directly with developers, open-source maintainers, startups, and large enterprises to uncover unmet needs and distinguish foundational opportunities from incremental improvements. Establish patterns and standards for reliability, observability, performance, experimentation, and evaluation across AI-powered developer workflows. Serve as a technical multiplier by reviewing critical designs, mentoring engineers, improving engineering practices, and helping the team navigate its hardest product and technical decisions. Contribute directly to implementation, particularly where the problem is novel, technically demanding, or requires connecting multiple layers of the product. You might thrive in this role if you Have led the design and delivery of technically complex, user-facing systems with impact extending beyond a single feature or team. Combine deep software-engineering expertise with exceptional product judgment and can move fluently across product interfaces, distributed systems, infrastructure, and developer tooling. Have a track record of creating clarity in ambiguous problem spaces, setting a compelling technical direction, and bringing multiple teams or disciplines along with you. Remain hands-on while increasing the effectiveness of other engineers through architecture, mentorship, decision-making, and technical leadership. Understand modern software-development workflows deeply and can recognize where AI agents require fundamentally new interaction and system designs. Have experience building or operating AI-powered products and understand the challenges created by nondeterminism, evaluation, latency, reliability, safety, and rapidly evolving model capabilities. Make thoughtful tradeoffs between speed, product learning, technical quality, and long-term leverage. Develop strong perspectives from user evidence while remaining willing to revise those perspectives as technology and user behavior evolve. Communicate clearly across engineering, product, design, research, and executive audiences, especially when decisions involve substantial uncertainty or organizational complexity. Are energized by defining a problem as much as solving it—and by creating the technical and organizational conditions for others to deliver excellent work. 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. 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