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# MODEL ENGINEER

- **Company:** Space X
- **Location:** United States
- **Salary:** $180,000.0
- **Contract:** Permanent contract
- **Skills:** C++ (Programming Language), Software Debugging, Distributed Systems, Python (Programming Language), Reinforcement Learning, Pytorch, Large Language Models, Production Code
- **Published:** November 1, 2026
- **Apply:** https://startup.jobs/model-engineer-rl-training-framework-xai-8750516

## About the Role

* Experience writing production-quality code in Python, PyTorch, JAX, Rust, or C++, * Experience building, debugging, and optimizing efficiency of large-scale distributed systems
 * Experience with large scale LLM training infrastructure
 * Strong knowledge of reinforcement learning techniques
 * Experience with RL numerics
 * Comfortable diving into unfamiliar areas and solving problems at all levels of the stack

## Description

* 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