Senior Backend / Full Stack Engineer

ABOUT THE ROLE Join a small engineering team building messaging infrastructure for AI agents. You will own complex systems from architecture through production, helping developers build reliable agent experiences across familiar communication interfaces. WHAT YOU'LL DO - Design and operate highly available backend services for large-scale, real-time messaging workloads. - Own projects end to end, including problem definition, architecture, implementation, deployment, observability, and ongoing operation. - Build intuitive APIs, SDKs, developer tools, dashboards, and internal platforms. - Address distributed systems challenges involving reliability, concurrency, fault tolerance, message delivery, queuing, and consistency. - Contribute across backend services, infrastructure, internal tooling, and user-facing developer experiences. - Evaluate technical tradeoffs and make pragmatic decisions that balance quality with execution speed. - Use AI coding agents thoughtfully while maintaining a strong understanding of code, architecture, and operational impact. - Take part in architecture discussions, code reviews, and incident analysis. WHAT WE'RE LOOKING FOR - At least 3 years of professional software engineering experience, including substantial experience building and operating production backend systems. - Strong proficiency in TypeScript and Node.js, plus experience with another backend language such as Go, Rust, or Swift. - Solid understanding of distributed systems, concurrency, networking, databases, and API design. COMPENSATION & BENEFITS Base salary is $100,000 to $200,000 annually, with meaningful equity. H-1B sponsorship and OPT and CPT support are available. LOCATION On-site in San Francisco, California.