Application Software Engineer, Inference

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 enabling human life on Mars. APPLICATION SOFTWARE ENGINEER, INFERENCE The application software team is the central nervous system of SpaceX – we create mission critical applications that are used throughout SpaceX to accelerate launch vehicle production and flight as well as systems that allow Starlink to grow into a worldwide fast, reliable Internet service. We are looking for engineers who treat fellow teammates with fairness, respect, and support. Our team maintains a high-performance AI inference platform that serves the best models internally at SpaceX to accelerate our most ambitious engineering goals. As part of this effort in Palo Alto, you will design and optimize large-scale model serving systems end-to-end, owning everything from distributed infrastructure to deep low-level optimizations. You will work on systems that deliver reliable, high-throughput inference to power SpaceX’s mission-critical applications while maintaining the highest standards of performance and availability. Aerospace experience is not required to be successful here - rather we look for smart, motivated, respectful, collaborative engineers who love solving problems and want to make an impact on a super inspiring mission. You will have full ownership of challenging problems, working with a team of enthusiastic engineers with diverse perspectives to design and produce solutions that enable SpaceX to achieve its loftiest engineering goals at a rapid pace. The success of the missions at SpaceX depends on the software that you and your team produce. This role will report through SpaceX Application Software while also working closely with xAI engineering teams. RESPONSIBILITIES: Develop highly reliable, high-throughput inference systems that serve the best AI models internally across SpaceX Architect and implement scalable distributed infrastructure for model serving, including load balancing, auto-scaling, batch scheduling, global KV cache, and continuous batching Optimize latency and throughput of model inference under real production workloads, including low-level GPU kernel work, quantization, speculative decoding, and other acceleration techniques Build reliable, high-concurrency serving systems with 100% uptime, low tail latency, and excellent observability Own end-to-end components such as request routing, SDK development, rate limiting, and efficient scaling for internal SpaceX AI inference platforms Benchmark, fine-tune, and accelerate inference engines (e.g., SGLang, vLLM, TensorRT-LLM) Develop custom tools for tracing, replaying, and resolving issues across the full stack — from orchestration down to GPU kernels Create robust CI/CD infrastructure for seamless endpoint deployment, image publishing, and inference engine updates Collaborate across SpaceXAI teams to integrate inference capabilities into broader systems and workflows BASIC QUALIFICATIONS: Bachelor's degree in computer science, engineering, math, or scientific discipline; OR 2+ years of professional experience building software in lieu of a degree Experience in designing, implementing, and maintaining reliable and horizontally scalable distributed systems 1+ years of experience in full stack development or backend development with production systems 1+ years of experience with Rust or C++ PREFERRED SKILLS AND EXPERIENCE: Experience with LLM inference engines and serving frameworks (e.g., SGLang, vLLM, Triton, TensorRT-LLM) Deep low-level systems programming and optimizations: GPU kernels, code generation, batching, caching, parallelism, quantization, and speculative decoding Experience with large-scale, high-concurrency production serving systems Knowledge of service observability and reliability best practices Experience operating commonly used databases such as PostgreSQL, ClickHouse, or MongoDB 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) Programming experience in Python, Go, or similar languages Experience with version control, continuous integration, continuous delivery, build systems, and monitoring Expertise in profiling and improving application performance ADDITIONAL REQUIREMENTS: You may be asked to work extended hours/weekends dependent on launch cadence and platform demands This role requires you to be onsite in Palo Alto. Remote and/or hybrid work will not be considered COMPENSATION AND BENEFITS: Pay Range: Software Engineer/Level I: $135,000.00 - $160,000.00/per year Software Engineer/Level II: $155,000.00 - $185,000.00/per year Your actual level and base salary will be determined on a case-by-case basis and may vary based on the following considerations: job-related knowledge and skills, education, and experience. Base salary is just one part of your total rewards package at SpaceX. You may also be eligible for long-term incentives, in the form of company stock, stock options, or long-term cash awards, as well as potential discretionary bonuses and the ability to purchase additional stock at a discount through an Employee Stock Purchase Plan. You will also receive access to comprehensive medical, vision, and dental coverage, access to a 401(k) retirement plan, short and long-term disability insurance, life insurance, paid parental leave, and various other discounts and perks. You may also accrue 3 weeks of paid vacation and will be eligible for 10 or more paid holidays per year. Employees accrue paid sick leave pursuant to Company policy which satisfies or exceeds the accrual, carryover, and use requirements of the law. ITAR REQUIREMENTS: To conform to U.S. Government export regulations, applicant must be a (i) U.S. citizen or national, (ii) U.S. lawful, permanent resident (aka green card holder), (iii) Refugee under 8 U.S.C. § 1157, or (iv) Asylee under 8 U.S.C. § 1158, or be eligible to obtain the required authorizations from the U.S. Department of State. Learn more about the ITAR here. SpaceX is an Equal Opportunity Employer; employment with SpaceX is governed on the basis of merit, competence and qualifications and will not be influenced in any manner by race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability or any other legally protected status. Applicants wishing to view a copy of SpaceX’s Affirmative Action Plan for veterans and individuals with disabilities, or applicants requiring reasonable accommodation to the application/interview process should reach out to EEOCompliance@spacex.com.