Principal Software Engineer, Agent Harness Bridge

Details

OpenAI's research training infrastructure powers how our frontier models are trained and evaluated. The Agent Harness Bridge team sits at the boundary between the Codex harness, research infrastructure, and internal agent systems, ensuring the same agentic coding runtime used in product can also support large-scale training workloads.

This team owns the integration layer that connects harness capabilities into the training stack. The work is highly cross-functional and high leverage: researchers depend on it to run reliably, platform teams depend on it to evolve cleanly, and failures in this surface can materially affect training velocity and correctness.

Responsibilities

• Design, build, and evolve the bridge between the Codex harness and research training infrastructure.
• Own major integration surfaces end-to-end, from architecture and API design through rollout, operations, and long-term maintenance.
• Build reliable, containerized execution systems that can support demanding training workloads at scale.
• Partner closely with research, agent, infrastructure, and platform teams to support new training use cases and harness capabilities.
• Design clean, stable interfaces and workflows for highly technical internal users who move quickly and expect strong ergonomics.
• Prevent one-off workarounds from becoming long-term technical debt by establishing durable abstractions and clear ownership.
• Raise the bar for correctness, reliability, operational rigor, and engineering judgment across a critical research-facing system.

Requirements

• Significant experience building and scaling backend or infrastructure systems in fast-moving environments.
• Deep strength in API design, systems design, and engineering fundamentals.
• Highly detail-oriented with a strong focus on correctness, reliability, and operational quality.
• Ability to work directly with demanding technical users while maintaining strong engineering discipline.
• Track record of leading cross-functional technical efforts and creating clarity across organizational boundaries.
• Strong product sense and user empathy for internal platforms and developer tooling.
• Motivated by enabling researchers and accelerating their work rather than doing research yourself.
• Proficient in Python and experience with backend platform engineering. Rust experience is a plus.

Location

This role is ideally based in San Francisco due to the close collaboration required with researchers and infrastructure partners.

Benefits

• 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.
• 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 coordinated company office closures.
• Mental health and wellness support; employer-paid basic life and disability coverage.
• Annual learning and development stipend; daily meals in offices and meal delivery credits as eligible.
• Relocation support for eligible employees.

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 AI capabilities and seek to safely deploy them through our products. We are an equal opportunity employer and provide reasonable accommodations to applicants with disabilities. Background checks for applicants will be administered in accordance with applicable law.