Senior Backend Engineer

Build and operate the backend systems that help AI agents reliably carry out work through connected tools. You will own core infrastructure across integrations, secure execution environments, and multi-tenant data, with a direct impact on product reliability and customer outcomes. What You’ll Do

• Design and operate a tool gateway that exposes connected APIs and MCPs through a composable Python SDK, including routing, authentication, rate limits, and reliability.
• Run persistent, isolated Linux sandboxes for workspaces, with attention to security, autoscaling, and cost.
• Build and maintain durable, high-performance data systems for multi-tenant workspace state and persistence.
• Find and resolve integration failures, then improve system design to prevent them from recurring.
• Work closely with company leadership and users to make technical decisions and deliver improvements quickly.

• 3 to 10+ years of experience building and operating production backend systems.
• Strong experience with distributed systems, production reliability, and designing for failure at scale.
• Hands-on expertise with sandboxing and OS-level isolation, including containers, Linux internals, and safely running untrusted code.
• Experience building Python services and working with infrastructure such as Modal.
• Practical experience with OAuth, webhooks, rate limits, and third-party API integrations.
• Experience designing multi-tenant systems, with strong instincts for durability, cost, and limiting the impact of failures.
• Background in infrastructure, platform, developer tools, or code execution systems, and an ability to learn and ship in a fast-moving environment.