Sr. Maching Learning Engineer, Search Ranking

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. SR. MACHINE LEARNING ENGINEER, SEARCH RANKING The X Search team is responsible for building and operating the core search engine that powers discovery on X. We own the full end-to-end search stack — from real-time retrieval and indexing to ranking and the end-user search experience. Our goal is to create the most relevant, fast, and intelligent search experience on the internet by combining state-of-the-art information retrieval systems with Grok’s reasoning capabilities. RESPONSIBILITIES: Build search and retrieval algorithms that scale to millions of users Build and operate large scale search engine and search infrastructure Train state of the art ML ranking models Integrate Grok in search systems and products BASIC QUALIFICATIONS: Experience in Python, Go, and Rust PREFERRED SKILLS AND EXPERIENCE: Experience with vector databases, search indices, or similar data stores for search applications Experience working on large-scale search systems Deep experience building or working with production ML systems Take full ownership of problems and learn whatever you need to solve them Can move quickly in a fast-paced environment with shifting priorities and tight deadlines COMPENSATION AND BENEFITS: $180,000 - $440,000 USD Base salary is just one part of our total rewards package at SpaceXSI, which also includes equity, comprehensive medical, vision, and dental coverage, access to a 401(k) retirement plan, short & long-term disability insurance, life insurance, and various other discounts and perks. SpaceXSI is an equal opportunity employer. For details on data processing, view our Recruitment Privacy Notice .