Back End Developer

Sr. Backend Engineer San Francisco, CA | $200K–$260K + equity Fast-growing, profitable AI infrastructure company seeking a Backend Engineer (3+ years) to own our guardrails and observability tooling at scale. You'll build for high-volume, mission-critical traffic and work directly with developers at large enterprise customers. You'll: • Build and scale our backend for reliability at massive volume • Own guardrails and logging code, ensuring traceability and clear error handling • Strengthen our observability stack for high-throughput, low-latency performance • Develop in Python and/or Rust, including CPU-level guardrails against common attacks • Engage directly with enterprise customer developers several times a week You have: • 3+ years backend engineering experience, ideally at a high-growth startup • Proficiency in Python or Rust • Experience with backend frameworks (FastAPI, Flask) and observability/monitoring tools • Familiarity with PostgreSQL and Redis • A CS degree or related technical field • Comfort with frequent customer interaction and a ~60 hr/week pace Good energy, hustle, and genuine excitement for startup life a must.