Sr. Backend Engineer, Enterprise

The role

You will build and maintain the unified inference stack and the platform services behind Chat API, Imagine API, Voice API, Grok Build and Grok Bot. You will also work on Chat API features, moderation and abuse protection, company-wide logging, and multi-region inference deployments.

What you will do

• Build and maintain the unified inference stack for all company inference needs
• Own and evolve platform services for Chat API, Imagine API, Voice API, Grok Build and Grok Bot
• Design, build and maintain Chat API features, including batch API, collections API and files API
• Implement and operate chat moderation and abuse protection across the API and grok.com
• Build and maintain company-wide logging for all request types, enforcing Zero Data Retention policies
• Manage multi-region inference cluster deployments, data aggregation, data replication and the distributed authentication system
• Take part in follow-the-sun on-call coverage (UK, Japan, US) for inference platform reliability

Required qualifications

• 5+ years of experience designing, implementing and maintaining reliable, horizontally scalable distributed systems
• Experience with Rust or C++

Nice to have

• Experience operating databases such as PostgreSQL, ClickHouse and CockroachDB
• Knowledge of service observability and reliability best practices
• Expert knowledge of Python
• Expert knowledge of TypeScript
• Experience with Docker, Kubernetes and containerized applications
• Expert knowledge of gRPC (unary, response streaming, bi-directional streaming, REST mapping)
• Hands-on experience with LLM APIs, embeddings or RAG patterns
• Track record of delivering user-facing software at scale

Before you apply

• SpaceXSI is an equal opportunity employer
• Recruitment data processing details are in the Recruitment Privacy Notice

About the company

SpaceXSI builds Super Intelligence to help humanity understand the universe, including Colossus supercomputers, Grok models and applications such as Grok Bot, Grok Build, Grok Imagine, Grok Voice and X. The Enterprise Agents Engineering Team builds applied AI solutions for business operations.