Sr. Model Engineer, RL Inference

SR. MODEL ENGINEER, RL INFERENCE

The RL infrastructure team is looking for an engineer to help with low precision RL training and inference.

RESPONSIBILITIES:

• Design and optimize our inference stack for all shapes of RL workloads at SpaceXSI, from small scale ablations to production training runs
• Analyze, profile and address performance bottlenecks in large scale RL systems
• Work closely with the modeling team to efficiently implement novel RL techniques and algorithms

BASIC QUALIFICATIONS:

• Experience writing production-quality code in Python, PyTorch, JAX, Rust, or C++
• Experience training large models (e.g., pre-training, post-training, fine-tuning, or RL training of neural networks with 1B+ parameters)

PREFERRED SKILLS AND EXPERIENCE:

• Experience in building, debugging, and optimizing efficiency of large-scale distributed systems
• Experience in LLM inference
• Strong knowledge in quantization and numerics in LLM inference and training
• Experience in developing inference engines, e.g. SGLang, vLLM
• Willingness to dive deep and solve hardcore problems at all levels of the stack

COMPENSATION AND BENEFITS:

$180,000 - $400,000 USD

Base salary is just one part of our total rewards package at SpaceXSI, which also includes equity, comprehensive medical, vision, and dental coverage, access to a 401(k) retirement plan, short & long-term disability insurance, life insurance, and various other discounts and perks.