Backend Engineer (API)

• Build the xAI API that serves our models to developers worldwide
• Own the end-to-end system responsible for high-throughput inference, handling billions of tokens per minute with low latency and high availability, including model serving infrastructure, request routing, SDK development, rate limiting, observability, and efficient scaling

Benefits

• Health and wellness: Comprehensive health insurance including medical, dental, vision, and disability coverage
• Life and family: Life and AD&D insurance and fertility benefits to ensure our team’s well-being and peace of mind
• Flexible vacation: We work hard but avoid burn out. Take time off when you need it
• Visa sponsorship: We support international talent with visa sponsorship to join our team
• 401(k) plan: Retirement savings plan to secure your financial future

• As an ideal candidate you have a good understanding of how highly scalable and reliable production infrastructure is built
• Most of our backend infrastructure is written in Rust. So familiarity with a compiled language such as C++, Rust, or Go is highly beneficial
• Experience in designing, implementing, and maintaining reliable and horizontally scalable distributed systems
• Expert knowledge of either Rust or C++
• Knowledge of service observability and reliability best practices
• Experience in operating commonly used databases such as PostgreSQL, Clickhouse, and MongoDB
• Experience designing or building with agent SDKs and agent orchestration frameworks
• Experience with LLM inference engines and serving frameworks (e.g., SGLang, TensorRT, vLLM)
• Experience with Docker, Kubernetes, and containerized applications
• Expert knowledge of gRPC (unary, response streaming, bi-directional streaming, REST mapping)