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 xAI 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
• Work on Linux kernel internals, scheduling, memory management, and resource isolation at cluster scale
• Build custom container orchestration, virtualization layers (KVM, Firecracker, etc.), and distributed systems that go beyond standard Kubernetes
• Profile, debug, and eliminate bottlenecks across GPU memory hierarchy, networking fabric, filesystems, and multi-GPU operations
• Create and maintain infrastructure-as-code, automation, and tools that keep the entire supercomputer reliable and efficient
• Collaborate closely with AI research teams to deliver production-grade performance and scalability

PREFERRED SKILLS AND EXPERIENCE:

• Deep low-level systems programming (C/C++ or Rust)
• Experience building and operating high performance exabyte scale storage systems
• Strong experience with large-scale GPU clusters or distributed compute infrastructure at production scale
• Hands-on work with GPU kernel optimization (CUTLASS, custom kernels, Nsight profiling)
• Experience with Linux kernel internals, scheduling, virtualization, or large-scale orchestration
• Track record of building or running high-performance infrastructure for AI workloads (training or inference platforms)
• Ability to reason from first principles and optimize for both memory-bound and compute-bound scenarios

COMPENSATION AND BENEFITS:

$180,000 - $440,000 USD

Base salary is just one part of our total rewards package at xAI, 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.

ABOUT THE ROLE:

xAI is building at a furious pace with the latest compute and switching hardware to help people understand the universe.  We are looking for exceptional ML Infrastructure Engineers with deep expertise in high-speed interconnect technologies to design, build, and optimize the network fabric that powers large-scale AI training and inference clusters.  This strategic role will drive innovation in high-bandwidth, low-latency, power-efficient interconnects critical for AI/ML clusters based on advanced computing platforms.

You will have the opportunity to work on all modalities of interconnects connecting GPUs and switches both inside and between data centers, including our primary front and backend networks that train Grok and that customers use for inference. Engineers will own all aspects from design and development to build and operations. You will be expected to define and improve team processes and to contribute to scaling and maintenance efforts.

You will focus on the physical layer and system-level integration of copper (ACC, AEC, CPC) and optical (FRO, LRO/TRO, LPO, AOC, CPO) interconnects that directly determine the performance, power efficiency, scale, and cost of next-generation AI/ML clusters.  This is a highly technical, hands-on role bridging ML cluster requirements with cutting-edge interconnect hardware — ideal for engineers who love both large-scale AI systems and the physics/engineering of 200G+ SerDes, PAM4, photonics, signal integrity and diagnostics.

RESPONSIBILITIES:

• Design, validate, and productize high-speed copper and optical connectivity solutions for AI clusters (100k+ GPU scale).
• Own vendor due diligence and onboarding for new 1.6T products including AEC and pluggable optical transceivers (DR4/8, FR4) including rigorous bring-up & characterization.
• Investigate the opportunity for LPO and LRO in our network.
• Evaluate early co-packaged and near-packaged engines for switches and GPUs.
• Pathfinding for new interconnect modalities including VCSEL, microLED, THz radio-based solutions to improve network economics and reliability.
• Work closely with vendors (transceiver, cable, SerDes, DSP, silicon photonics foundries) to influence roadmaps and ensure timely delivery of next-gen solutions.
• Collaborate with ML training teams to translate workload communication patterns into concrete interconnect topology and optical reconfigurability requirements.
• Perform system-level simulation of end-to-end fabric performance.
• Drive failure analysis, root cause, and corrective actions for interconnect-related issues in production clusters through fleet-level metrics gathering and analysis.
• Contribute to internal tooling and automation for interconnect health monitoring, telemetry, diagnostics, remediation and automated qualification pipelines.
• Stay current with industry standards (OIF CMIS, IEEE) and emerging technologies (multi-core/hollow-core fiber, 448G SerDes, TFLN, ring resonators)

BASIC QUALIFICATIONS:

• At least 8+ years of hands-on experience in designing, deploying and operating high-speed copper and optical interconnects, preferably in a module design role or in a hyperscale datacenter environment.
• Master's or PhD degree in Electrical Engineering, Photonics or Physics.
• Deep knowledge of PAM4 SerDes performance, equalization, jitter, crosstalk.
• Solid operational understanding of FEC, Retimers, TIAs and Drivers.
• Deep knowledge of optical link budget analysis and performance metrics including TDECQ, OMA, Tcode, stressed receiver sensitivity and associated diagnostics.
• Expertise in transceiver components including CW lasers, SiPh PICs, EML, DSP, passive subassemblies, their failure modes and characterization.
• Knowledge of thermal, mechanical, power, signal integrity constraints in dense hardware.
• Knowledge of SiPh design process, yield improvement and reliability testing.
• Familiarity with CPO technologies and challenges/risk areas.
• Familiarity with subcomponent supply chains and global manufacturers, ODMs and CMs.
• Strong problem-solving skills and ability to thrive in a fast-paced, ambiguous setting.

COMPENSATION AND BENEFITS:

$180,000 - $440,000 USD

Base salary is just one part of our total rewards package at X, 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.

ABOUT THE ROLE:

We are looking for a Developer Experience Engineer to join our team at xAI. This role combines deep technical contributions with direct community engagement to make xAI's tools and APIs accessible, powerful, and loved by developers worldwide. You will act as a bridge between our core engineering efforts and the broader developer ecosystem, contributing code, documentation, and examples that accelerate adoption of Grok and xAI's models.

At xAI, we build AI to accelerate human scientific discovery and advance our collective understanding of the universe. Developer Experience here is hands-on and outcome-driven: you ship real code to open source repos, solve actual developer pain points, and influence product direction through community insights and your own prototypes.

RESPONSIBILITIES:

• Contribute to and maintain popular open source SDKs and repositories for xAI, including pushing high-quality code, reviewing PRs, and evolving libraries that power developer integrations with our models.
• Write clear, comprehensive documentation that empowers developers to build with Grok quickly and effectively.
• Engage directly with the community — on X, Discord, GitHub, forums, and beyond — answering questions, gathering feedback, and turning insights into actionable improvements.
• Create and ship practical examples, tutorials, reference apps, and demos that showcase best practices for using xAI APIs in real-world scenarios.
• Collaborate closely with engineering, product, and research teams to identify friction in developer workflows and drive fixes or new features.
• Help shape how developers experience xAI in an era of rapid AI advancement, focusing on speed, reliability, and innovation.

BASIC QUALIFICATIONS:

• Open source maintainer or core contributor with a track record of shipping meaningful code to public repositories that others rely on.
• Strong Typescript fullstack expertise and can build end-to-end solutions confidently.
• Previous experience in DevRel, Developer Advocacy, Developer Experience, or a closely related role where you owned community-facing technical work.

PREFERRED SKILLS AND EXPERIENCE:

• Hands-on experience with Next.js / React for building modern web interfaces and apps.
• Experience building agents in Python
• Background as an indie hacker, ex-founder, or solo builder who has shipped products independently and understands developer needs from personal experience.
• We move fast, prioritize impact over process, and expect high ownership. If you're excited to make xAI the go-to platform for developers building with frontier AI, we'd love to hear from you. Apply with your GitHub profile, notable open source contributions, or examples of community work you've done.

ABOUT THE ROLE:

In this role you will work on xAI's production systems that power the API. The actual team matching will happen at the offer stage.

As an ideal candidate you have a good understanding of how highly scalable and reliable production infrastructure is built. You strive for perfection and listen carefully to your users in order to solve any pain points they might experience. Most of our backend infrastructure is written in Rust. So familiarity with a compiled language such as C++, Rust, or Go is highly beneficial.

BASIC QUALIFICATIONS:

• Expert knowledge of either Rust or C++,
• Experience in designing, implementing, and maintaining reliable and horizontally scalable distributed systems,
• Knowledge of service observability and reliability best practices,
• Experience in operating commonly used databases such as PostgreSQL, Clickhouse, and MongoDB.

PREFERRED SKILLS AND EXPERIENCE

• Knowledge of Python,
• 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.

ABOUT THE ROLE:

The Sandbox service team at xAI builds and maintains a secure, scalable system that gives our models safe, controlled access to computational environments. This infrastructure powers critical workloads across training and product, enabling models to run code, build software, interact with tools, and even control applications with user interfaces. We provision containers and virtual machines on large-scale clusters, granting models interactive control over these remote environments. Our work spans the full stack: from orchestrating massive jobs and resource scheduling at the cluster level, to fine-tuning filesystem performance on nodes. The Sandbox service enables Grok to safely run and test code in real-time for user queries, and supports reinforcement learning in training, where models interactively explore tools ranging from compilers to productivity apps.

BASIC QUALIFICATIONS:

• Expert knowledge of Rust, C++ or Go
• Familiarity with Python
• Deep experience with either Linux or Windows systems (familiarity with both is a strong plus)
• Experience with virtualisation and containerisation technologies (e.g., cgroups, KVM, gVisor, QEMU)
• Solid knowledge of the networking stack

ABOUT THE ROLE:

We’re looking for exceptional storage & database engineers who want to join us on a new project to deeply integrate xAI’s advanced AI infrastructure into a platform used by around 600 million users every month. We’re building xAI’s 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 in a collaborative environment and uplevel your peers by doing mentoring, code and design reviews.
• Be open to develop new skills and learn on the job as we navigate new technology spaces.
• Ground your decisions with data and reasoning and adapt to new information to make informed choices.

BASIC QUALIFICATIONS:

• Have at least 7 years of experience in software development, plus 2+ years building storage systems or databases.
• Obsessed with reliability, performance, and quality
• Proficient in high performance C++, Rust, or JVM-based languages
• Expertise in building, running, and operating scalable and resilient distributed systems

COMPENSATION AND BENEFITS:

$180,000 - $440,000 USD

Base salary is just one part of our total rewards package at xAI, 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.

About the Role:

• We are building the high-performance inference platform that serves Grok to millions of users every day with lightning speed and perfect reliability.
• As a Member of Technical Staff - Inference, you will design and optimize large-scale model serving systems end-to-end. You will own everything from distributed infrastructure (global KV cache, continuous batching, load balancing, auto-scaling) to deep low-level optimizations (GPU kernels, quantization, speculative decoding, tail latency).
• This is a high-impact role where your work directly determines how fast and reliably users interact with Grok at massive scale

Responsibilities: 

• Architect and implement scalable distributed infrastructure for model serving (load balancing, auto-scaling, batch scheduling, global KV cache).
• Optimize latency and throughput of model inference under real production workloads.
• Build reliable, high-concurrency serving systems that serve billions of users with 100% uptime, 0% error rate, and excellent tail latency.
• Benchmark, fine-tune, and accelerate inference engines (including low-level GPU kernel work and code generation).
• Develop custom tools to trace, replay, and fix 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.
• Accelerate research on scaling test-time compute, RL rollout, and model-hardware co-design for next-generation systems.

BASIC QUALIFICATIONS:

• Deep low-level systems programming (C/C++ or Rust)
• Experience with large-scale, high-concurrent production serving.
• Experience with GPU inference engines (vLLM, SGLang, Triton, TensorRT-LLM, etc.).
• Strong background in system optimizations: batching, caching, load balancing, parallelism.
• Low-level inference optimizations: GPU kernels, code generation.
• Algorithmic inference optimizations: quantization, speculative decoding, distillation, low-precision numerics.
• Experience with testing, benchmarking, and reliability of inference services.
• Experience designing and implementing CI/CD infrastructure for inference.

COMPENSATION AND BENEFITS:

$180,000 - $440,000 USD

Base salary is just one part of our total rewards package at xAI, 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.

ABOUT THE ROLE:

You will work on the team that is responsible for the backend services that power our products such as grok.com and the API. We focus on writing and maintaining highly scalable and reliable services that can efficiently process tens of thousands of queries per second. The services are hosted on a number of Kubernetes clusters (on-prem & cloud).

BASIC QUALIFICATIONS:

• Expert knowledge of Kubernetes.
• Expert knowledge of continuous deployment systems such as Buildkite and ArgoCD.
• Expert knowledge of monitoring technologies such as Prometheus, Grafana, and PagerDuty.
• Expert knowledge of infrastructure as code technologies such as Pulumi or Terraform.
• Familiarity with a systems programming language like Rust, C++ or Go
• Experience with traffic management and HTTP proxies such as nginx and envoy.

ABOUT THE ROLE:

xAI was first in the world to build a 100k GPU cluster on an ethernet network and then did it again in 92 days, floors, walls and all. We need an engineer with deep experience in RoCEv2 that can develop at hyper scale while optimizing performance and availability. 

xAI is building at a furious pace with the latest hardware to help people understand the universe. To make the next significant leap forward, we need to own our own destiny by understanding our current network performance and availability and then optimize it to our training models and how we execute customer inference queries. You will spend most of your days deep inside  NCCL, building metric dashboards and tweaking configurations to ensure no performance is left on the table. You will help design the next iteration of our backend and front-end networks that will allow us to seamlessly build-out new GPU infrastructure with little to no engineering assistance.  

There will be a significant amount of travel to Memphis for building more capacity as well as participating in a team on-call rotation and helping on other scaling and maintenance efforts. This will become easier as we build out the team and engineers contribute to deployment and operations frameworks to remove repetitive tasks.

BASIC QUALIFICATIONS:

• A minimum of 10 years designing and operating large scale networks with 5 years in the ethernet AI/HPC space.
• Deep understanding of congestion control on ethernet with Infiniband an added bonus.
• Deep understanding of AI training and inference workloads and how they operate on the network. As part of this you are able to use and debug NCCL and potentially commit to the library.
• Expertise in creating a portfolio of metrics for performance and operations to optimize the fleet for training and inference traffic.
• Experience with Python to automate away repetitive tasks and facilitate your daily job working with and analyzing large sets of data.