Member of Technical Staff — Kernel/Compiler/Communication

Responsibilities

• Design and implement high-performance kernels for AI workloads
• Optimize compiler and runtime stacks for ML systems
• Improve communication efficiency across large GPU clusters
• Reduce latency and increase throughput for distributed workloads
• Profile and eliminate system bottlenecks across the stack
• Collaborate with training and inference teams on performance optimization
• Develop tooling for profiling and performance analysis
• Contribute to long-term architecture for performance-critical systems
• Push the limits of hardware–software co-design

Requirements

• 5+ years of experience in systems, compiler, or performance engineering
• Strong expertise in CUDA or accelerator programming
• Deep understanding of GPU architecture and memory hierarchy
• Experience writing or optimizing high-performance kernels
• Strong background in compilers, runtimes, or code generation
• Experience with distributed communication libraries (NCCL, MPI, RCCL, etc.)
• Solid knowledge of networking and interconnect technologies
• Proficiency in C++ and Python
• Strong debugging and profiling skills at system level

Preferred Qualifications

• Experience with Triton, TVM, XLA, or MLIR
• Experience building compiler passes or IR transformations
• Familiarity with NVLink, InfiniBand, or RDMA
• Experience optimizing collective communication at scale
• Background in HPC or performance-critical systems
• Contributions to kernel/compiler/ML systems open source
• Experience scaling workloads to 1000+ GPUs
• Experience with mixed-precision or quantized kernels

About the Company

RadixArk is an infrastructure-first company built by engineers who've shipped production AI systems, created SGLang, and developed Miles. We're on a mission to democratize frontier-level AI infrastructure by building world-class open systems for inference and training.