Software Engineer Kernels CUDA C++
SpaceXAI builds frontier AI models and products including the Grok conversational assistant and a multimodal developer API.
Funding history
About SpaceXAI
SpaceXAI is a US-based AI company focused on accelerating scientific discovery and understanding the universe through reasoning, voice, image, video, and generative AI systems. Formerly xAI, it was acquired by SpaceX effective February 2, 2026, while continuing to operate the x.ai site and services.
Skills
Candidate Availability
Required and preferred rules are kept separate and reflect the wording in the original posting.
About the Role
You will design, build, and optimize GPU clusters for training and inference. You will develop CUDA kernels, profile and remove bottlenecks across GPU memory, networking, filesystems, and multi-GPU operations, and deliver production-grade performance and scalability with research teams.
Requirements
- Low-level systems programming knowledge in C, C++, PTX, or SASS
- Experience with large-scale GPU clusters or distributed compute infrastructure
- Experience with GPU kernel optimization using CUTLASS, custom kernels, or Nsight profiling
- Experience building or running high-performance infrastructure for AI training or inference workloads
- Ability to optimize memory-bound and compute-bound scenarios
Responsibilities
- Design, build, and optimize GPU clusters for training and inference workloads
- Develop and tune low-level CUDA kernels
- Profile, debug, and eliminate bottlenecks across GPU memory, networking, filesystems, and multi-GPU operations
- Collaborate with AI research teams to deliver production-grade performance and scalability
Benefits
- Equity
- Medical coverage
- Vision coverage
- Dental coverage
- 401(k) retirement plan
- Short-term disability insurance
- Long-term disability insurance
- Life insurance
- Discounts and perks