Senior RL Training Framework Engineer

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

Benefits offered by this job

Equity

Medical, vision, dental

401(k) retirement plan

Disability insurance

Life insurance

Job summary

SpaceXSI in Palo Alto is seeking a Sr. Model Engineer to join our RL Training Framework team. You will design and implement the systems backing RL workloads, from small-scale ablations to production training runs, in a high-performance stack.

You will profile, debug, and optimize end-to-end training performance, and improve scalability and observability of the RL stack, enabling 1B+ parameter models and beyond. The role offers a competitive package with equity and comprehensive benefits.

Qualifications

• Experience writing production-quality code in Python, PyTorch, JAX, Rust or C++.
• Experience training large models (1B+ parameters) including RL training.
• Experience building, debugging, and optimizing large-scale distributed systems.

Responsibilities

• Design and implement the systems backing all RL workloads at SpaceXSI, from small scale ablations to production training runs.
• Profile, debug, and optimize end-to-end training performance.
• Improve scalability and observability of the RL stack.

Skills

Python

PyTorch

JAX

Rust

C++

Distributed systems

LLM training

RL techniques

Job description

SpaceXSI in Palo Alto is seeking a Sr. Model Engineer to join our RL Training Framework team. You will design and implement the systems backing RL workloads, from small-scale ablations to production training runs, in a high-performance stack.

You will profile, debug, and optimize end-to-end training performance, and improve scalability and observability of the RL stack, enabling 1B+ parameter models and beyond. The role offers a competitive package with equity and comprehensive benefits.