Hiring Sea

xAI

Posted Dec 17, 2025

Open position

Sr. Backend Engineer, Enterprise

JapanOn-site5+ yrs
Checking your account…

About the role

SpaceX was founded under the belief that a future where humanity is out exploring the stars is fundamentally more exciting than one where we are not. Today, SpaceX is actively developing the technologies to make this possible, with the ultimate goal of making life multiplanetary and expanding consciousness to the stars.

SpaceXSI is building Super Intelligence to help humanity understand the universe. Our teams are building the full Super Intelligence stack: from our Colossus supercomputers, to Grok models, to our suite of applications, including Grok Bot, Grok Build, Grok Imagine, Grok Voice, and X. We're creating a powerful flywheel where more compute trains better models, better models power more useful products, and what we learn from people using those products shapes what we build next.

BACKEND ENGINEER, ENTERPRISE

The Enterprise Agents Engineering Team at SpaceXSI is a team of builders solving the hardest problems in applied AI: integrating with messy systems, orchestrating complex workflows, and harnessing AI to transform business operations. We build full-stack solutions with ownership of end-to-end product execution from ideation to deployment, collaborating closely with our team to incorporate cutting-edge AI advancements into robust and reliable user-centric solutions. Through an iterative development process, we work hand-in-hand with customers to gather feedback, refine features, and evolve products to address real-world challenges.

RESPONSIBILITIES:

Build and maintain the unified inference stack as the single surface area for all inference needs across the company

Own and evolve the platform services that power Chat API, Imagine API, Voice API, Grok Build, and Grok Bot

Design, build, and maintain Chat API features including batch API, collections API, files API, and related capabilities

Implement and operate chat moderation and abuse protection systems across the API and grok.com

Build and maintain the company-wide logging system for all request types, including enforcement of Zero Data Retention (ZDR) policies

Manage multi-region inference cluster (IC) deployments, data aggregation, data replication, and the distributed authentication system

Participate in follow-the-sun on-call coverage (UK → Japan → US) to ensure continuous reliability of the inference platform

BASIC QUALIFICATIONS:

5+ years of experience in designing, implementing, and maintaining reliable and horizontally scalable distributed systems

Experience with Rust or C++

PREFERRED SKILLS AND EXPERIENCE:

Experience with 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

SpaceXSI is an equal opportunity employer. For details on data processing, view our Recruitment Privacy Notice .

Skills

C++DockerKubernetesLLMsPostgreSQLPythonRESTRustTypeScriptgRPC