Backend Engineer - API
xAI· Engineering
Hybrid (London)£107k - £262kfull-timePosted 6mo ago
About the role
Backend Engineer role focusing on building the SpaceXSI API and end-to-end high-throughput inference infrastructure for model serving, with emphasis on scalable, reliable production systems using Rust/C++/Go. London-based.
Responsibilities
- Build the SpaceXSI 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
Qualifications
- Expert knowledge of either Rust or C++
- Experience in designing, implementing, and maintaining reliable and horizontally scalable distributed systems
- Knowledge of service observability and reliability best practices
- Experience in operating commonly used databases such as PostgreSQL, Clickhouse, and MongoDB
Skills
Required:Rust or C++ expertDistributed systems designObservability and reliabilityDatabase experience
Nice to have:LLM inference and serving (preferred)Agent SDKs and orchestration (preferred)Docker/Kubernetes (preferred)gRPC expertise
Benefits
- equity
- comprehensive healthcare and dental coverage
- cash plan
- income protection
- life insurance
- various other discounts and perks
Last updated Oct 14, 2026. Interested? Apply on the company site.
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