Senior RL Training Systems Engineer

SpaceXSI; Palo Alto (CA); On-site; USD 180,000 - 400,000; Full time

Benefits offered by this job

Equity

Medical

Vision

Dental

401(k)

Disability Insurance

Life Insurance

Discounts & Perks

Job summary

SpaceXSI in Palo Alto is seeking a Senior Model Engineer to build and maintain the RL training framework that powers our Grok models. You will work on scalable RL infrastructure, from small experiments to production training runs, partnering with teams across our stack to push frontline AI capabilities.

The role demands strong software engineering skills, experience with Python and modern ML frameworks, and a passion for optimizing performance, efficiency, and reliability in large-scale

Qualifications

• Production-quality code experience in Python, PyTorch, JAX, Rust or C++.
• Experience training large models (1B+ parameters) including RL training.

Responsibilities

• Design and implement the RL training framework and supporting systems.
• Profile, debug, and optimize end-to-end RL training performance.
• Improve scalability and observability of the RL stack.

Skills

Python

PyTorch

JAX

Rust

C++

Large-scale model training

Job description

SpaceXSI in Palo Alto is seeking a Senior Model Engineer to build and maintain the RL training framework that powers our Grok models. You will work on scalable RL infrastructure, from small experiments to production training runs, partnering with teams across our stack to push frontline AI capabilities.

The role demands strong software engineering skills, experience with Python and modern ML frameworks, and a passion for optimizing performance, efficiency, and reliability in large-scale