Senior Staff Software Engineer, API

<div class="content-intro"><h2><strong>About Anthropic</strong></h2> <p>Anthropic’s mission is to create reliable, interpretable, and steerable AI systems. We want AI to be safe and beneficial for our users and for society as a whole. Our team is a quickly growing group of committed researchers, engineers, policy experts, and business leaders working together to build beneficial AI systems.</p></div><h2 class="heading"><strong>About the role</strong></h2> <p>Anthropic is seeking an exceptional Senior Staff Software Engineer to join the Claude Developer Platform team and serve as the senior-most individual contributor across API Engineering. Since launch, the Claude API has seen rapid growth and adoption by companies of all sizes to build AI applications with our industry-leading models. The API serves as the primary channel for safely and broadly distributing AI's benefits across all sectors of the economy.</p> <p>This role sets the technical direction for the systems that make Claude accessible to developers, enterprises, and partners at scale. You will operate at the intersection of technical strategy and execution, partnering closely with Research, Inference, Platform, Infrastructure, and Safeguards to ensure the Claude API is reliable, capable, and positioned to grow with Anthropic's ambitions.</p> <p>This is a high-agency role that spans all API Engineering teams: <strong>API Core</strong> owns the foundational reliability and performance of the Claude API; <strong>API Capabilities</strong> ships frontier model capabilities—vision, tool use, computer use—directly to developers; <strong>API Knowledge</strong> builds retrieval and grounding systems that let Claude reason over external data; <strong>API Distributability</strong> ensures Claude reaches customers wherever they need it, with the enterprise-ready infrastructure to support it; and <strong>API Agents</strong> builds the infrastructure for long-horizon agentic workflows in production.</p> <h2 class="head