Software Engineer (Sandbox Service)

• 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

Benefits

• Health and wellness: Comprehensive health insurance including medical, dental, vision, and disability coverage
• Life and family: Life and AD&D insurance and fertility benefits to ensure our team’s well-being and peace of mind
• Flexible vacation: We work hard but avoid burn out. Take time off when you need it
• Visa sponsorship: We support international talent with visa sponsorship to join our team
• 401(k) plan: Retirement savings plan to secure your financial future

• Solid knowledge of the networking stack
• 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)
• Candidates must be willing to attend late meetings at least once a week to coordinate with the rest of our team in Palo Alto

• After submitting your application, the team reviews your statement of exceptional work and CV. If your application passes this stage, the interview process is as follows:
• Initial technical screening during which a member of our team will ask some basic technical questions (15 minutes)
• Coding interview in either Rust / C++ / Go / Python (45 minutes)
• Distributed systems design (45 minutes)
• Final stage with founding engineer Toby Pohlen (30 minutes)
• All interviews will be conducted via Google meet