Staff Software Engineer, Environments Infrastructure

Anthropic's Environments organisation builds and maintains infrastructure that improves Claude's capabilities through reinforcement learning. You will embed with research teams, design frameworks and APIs, and productionize research.

Key responsibilities:

• Design widely used APIs, frameworks, and abstractions for other engineers and researchers.
• Own platform layers beneath every environment, including the agent runtime.
• Build tooling for environment owners to understand, debug, and maintain their environments in production.
• Embed with research teams on a rotational basis and transfer ownership when rotating off.
• Anticipate and prevent silent failure modes through type safety, testing, and refactors.
• Drive adoption of new frameworks across the organisation.
• Help define engineering standards and mentor researchers and engineers.

Minimum qualifications:

• Deep expertise in Python, including static typing and safe async patterns.
• Strong taste in API and framework design.
• Experience designing or operating stateful concurrent or distributed systems.
• Habit of verification: measuring before concluding and building checks for correctness.
• Experience working productively in large, evolving codebases.
• Strong written and verbal communication.

Preferred qualifications:

• Experience building infrastructure or frameworks for machine learning research or RL workflows.
• Experience building agent frameworks, orchestration engines, or multi-agent systems.
• Experience using AI coding tools on code where correctness matters.
• Experience building client libraries or SDKs on top of sandboxed platforms.
• Experience with large-scale data processing or dataset lifecycle management.

The annual compensation range for this role is $405,000-$605,000 USD.