Senior AI Kernel Engineer

About Modular

About the role:

What you will do:

• Design, implement, and optimize performance-critical kernels for AI inference workloads (e.g., GEMM, attention, communication, fusion).
• Lead kernel-level optimization efforts across single-GPU, multi-GPU, and heterogeneous hardware environments.
• Make informed trade-offs between latency, throughput, memory footprint, and numerical precision.
• Drive adoption of new hardware features (e.g., Tensor Cores, asynchronous execution, advanced memory spaces).
• Analyze performance using profilers, hardware counters, and microbenchmarks; translate insights into concrete improvements.
• Work closely with compiler and runtime teams to influence code generation, scheduling, and kernel fusion strategies.
• Review and mentor other engineers on kernel design, performance tuning, and best practices.
• Contribute to technical roadmaps and long-term performance strategy for AI inference.

What you bring to the table:

• 5+ years of experience in performance-critical systems or kernel development (or equivalent depth of expertise).
• Strong proficiency in C/C++ and low-level programming.
• Extensive hands-on experience with GPU kernel programming (CUDA, HIP, or equivalent).
• Deep understanding of GPU architecture, including memory hierarchies, synchronization, and execution models.
• Proven track record of delivering measurable performance improvements in production systems.
• Strong problem-solving skills and ability to work independently on complex, ambiguous performance challenges.

 Helpful, but not required:

• Experience with PTX, assembly-level tuning, or code generation frameworks (e.g., Triton).
• Experience optimizing distributed or multi-GPU inference pipelines.
• Familiarity with custom AI accelerators or domain-specific hardware.
• Understanding of modern AI models (e.g., transformers, LLMs, diffusion) from a systems and performance perspective.
• Contributions to open-source kernel libraries, compilers, or performance tools.
• Experience collaborating directly with hardware or compiler teams.

What Modular brings to the table:

• Amazing Team. We are a progressive and agile team with some of the industry’s best engineering and product leaders.
• World-class Benefits. In order to attract the best, we need to offer the best. Premier insurance plans, up to 5% 401k matching, flexible paid time off, and more are available to you! Please note that specific benefit packages may vary based on your location.
• Competitive Compensation. We offer very strong compensation packages, including stock options. We want people to be focused on their best work and believe in tailoring compensation plans to meet the needs of our workforce. 
• Team Building Events. We organize regular team onsites and local meetups in Los Altos, CA as well as different cities. Traveling 2-4 times a year is expected for all roles.