Software Engineer - Network (C++)

About this role

xAI is seeking a Software Engineer to develop core networking software for Colossus, a massive GPU cluster powering frontier AI models. You'll design routing algorithms, build real-time switch software, and own the full lifecycle of high-performance datacenter networking systems from design through production deployment.

What you'll do

• Develop routing and traffic-engineering algorithms for high-performance datacenter networks
• Build reliable, real-time software for switches in low-latency AI training fabric
• Lead architecture, design, and code reviews
• Create prototypes and validate designs at cluster scale
• Build tools for deployment, testing, and monitoring across virtualized and production environments
• Deploy software updates through continuous integration with rigorous testing

What they're looking for

• C/C++ development
• High-performance systems programming
• Networking protocols (TCP/IP, UDP, RDMA)
• Distributed systems
• Real-time systems
• Debugging and deploying at scale
• Problem-solving and analytical thinking
• Communication skills

Benefits

• Competitive salary ($180,000 - $440,000)
• Equity compensation
• Comprehensive medical, vision, and dental coverage
• 401(k) retirement plan
• Short and long-term disability insurance
• Life insurance