Backend Engineer - API

Xai · London, England, United Kingdom · Engineering

Posted 2026-09-10

Apply for this role →

ABOUT THE ROLE:

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.

RESPONSIBILITIES:

Build the SpaceXAI 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

BASIC 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

PREFERRED SKILLS AND EXPERIENCE:

Experience with LLM inference engines and serving frameworks (e.g., SGLang, TensorRT, vLLM)

Experience designing or building with agent SDKs and agent orchestration frameworks

Experience with Docker, Kubernetes, and containerized applications

Expert knowledge of gRPC (unary, response streaming, bi-directional streaming, REST mapping)

COMPENSATION AND BENEFITS:

£107,000 - £262,000 GBP

Base salary is just one part of our total rewards package at SpaceXAI, which also includes equity, comprehensive healthcare and dental coverage, cash plan, income protection, life insurance, and various other discounts and perks.

Apply for this role →

← Back to all jobs