Software Engineer - Linux Kernel (C++, C)

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. RESPONSIBILITIES: Design, build, and implement a large-scale distributed system that powers one of the world's largest supercomputing clusters. Dive into the low-level stack to profile, debug, and optimize performance across diverse systems, including GPUs, Linux kernel, networking, and filesystems, to achieve peak efficiency. Collaborate on hardware, software, and algorithm co-design to push the boundaries of AI training. Maintain and innovate on our codebase to ensure scalability and reliability. Develop tools to enhance team productivity and streamline workflows. BASIC QUALIFICATIONS: Systems programming experience in C, C++, or Rust Computer systems fundamentals with a grasp of how computers execute code from transistors to high-level applications. Hands-on expertise with Kubernetes (K8s), including cluster architecture, pod lifecycle, networking (CNI), storage (CSI), service mesh, and production-grade operations PREFERRED SKILLS AND EXPERIENCE: Collaborate in a fast-paced, open environment to design and foundational systems. Strong debugging skills across the full stack — from kernel and OS up through container orchestration layers Deep knowledge of operating systems intern

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. ABOUT THE ROLE: We are building one of the world’s largest AI supercomputers from the ground up. As part of the Compute Infrastructure team, you will own both the raw GPU supercomputer and the platform layer that runs on top of it. You will work across the full stack — from low-level GPU kernel optimizations and Linux kernel internals to massive-scale orchestration and virtualization — to make training and inference at SpaceXSI as fast, reliable, and scalable as possible. This is a broad, high-impact role that combines hardcore supercompute and compute infrastructure work. Your contributions will directly accelerate Grok’s training speed and overall AI progress. RESPONSIBILITIES : Design, build, and optimize massive GPU clusters for extreme-scale training and inference workloads Develop and tune low-level CUDA kernels (GeMM, Attention, etc.), using CUTLASS, Tensor Cores, and Nsight for maximum performance Profile, debug, and eliminate bottlenecks across GPU memory hierarchy, networking fabric, filesystems, and multi-GPU operation Collaborate closely with AI research teams to deliver production-grade performance and scalability PREFERRED SKILLS AND EXPERIENCE: Deep low-level syst

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. ABOUT THE ROLE: As an engineer for Consumer Subscriptions (X Premium & SuperGrok), you will own the entire billing and monetization infrastructure powering one of SpaceXSI's fastest-growing revenue organizations. You will build and lead the dedicated engineering team responsible for subscriptions, promotions, global payments, and personalized user experiences at massive scale. This high-impact engineering role offers the opportunity to directly drive significant revenue growth while architecting systems that serve hundreds of millions of users worldwide and shape the future of premium AI and social products. RESPONSIBILITIES: Own the complete billing infrastructure for consumer subscriptions end-to-end, ensuring world-class reliability, security, and scalability. Design and build sophisticated promotional offer infrastructure and internal tools to supercharge the revenue organization. Develop comprehensive communications systems enabling intelligent push, email, and in-app messaging that drive engagement and conversions. Implement market-specific billing methods and compliance solutions to accelerate global expansion. Architect compelling product bundles across the X ecosyst

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. ABOUT THE ROLE: As a Data Engineer in X product engineering team, you will play a key role in providing comprehensive data solutions that own or serve a wide range of stakeholders, including our end-users and internal teams such as Product engineering, Algorithm, Legal, Finance and Sales. Our work utilizes AI, distributed computing and hybrid storage technologies, but extends beyond purely data-centric solutions, encompassing non-data-related challenges, ultimately maximizing the potential of data for the benefit of our diverse user base. RESPONSIBILITIES: You'll help build and operate a distributed data platform that powers hundreds of realtime and batch pipelines processing billions of events per day. The team runs like an internal startup — we own problems end to end, from raw event streams to the datasets, tooling, and metrics that product, growth, safety, and business teams depend on daily. In this role you will: Design, build, and operate production-grade realtime and batch pipelines that ingest, process, validate, and deliver data powering user-behavior insights and product decisions. Create shared datasets, fact tables, and internal data products that let other teams ana

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. You will own and elevate our mission-critical research platform that directly accelerates SpaceXSI's frontier work. The evals team creates and executes instruments for measuring model capabilities and behaviors. These instruments are used to clean datasets, provide feedback for experiments, and track growth throughout training. The evals team also diagnoses why agents fail and how to make improvements both short and long term. We manage the execution infrastructure, design data sets and grading schemes. You will design, build, and ship delightful and bulletproof systems that engineers love to use every day. This role values a strong attention to details, first principles reasoning, and great taste. We are open to all levels from new grads to senior engineers. Requirements Software engineering proficiency and 3+ years of experience actively writing code. A track record of shipping high quality projects and a strong sense of urgency. Exceptional product taste - you have a sharp sense for what “good” looks like in outputs, and you can translate fuzzy notions of quality, helpfulness, truthfulness, and safety into concrete, measurable criteria. Strong attention to d

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. ABOUT THE ROLE: We’re looking for exceptional storage & database engineers who want to join us on a new project to deeply integrate SpaceXSI's advanced AI infrastructure into a platform used by around 600 million users every month. We’re building a new storage tier that powers training, inference, recommendations, and real-time data extraction. We build and operate: An exabyte-scale S3-compatible object store A multi-tenant transactional key/value store that serves 100s of millions requests per second A caching tier that serves billions of requests per second A scalable vector database that powers our recommendation systems A few other specialized databases serving hundreds of millions requests per second RESPONSIBILITIES: Design, build, and launch to production new features and improvements aimed at unifying common components across the storage systems Dive into performance issues and work with customers and deliver solutions to cater to customers’ latency, availability and data durability requirements. Lead and drive incident responses and recovery with your peers. Review and contribute to incident postmortems and hold a high bar for the same. Work