xAI Sr. Model Engineer at xAI focusing on post-training and reinforcement learning challenges including reward modeling and preference optimization. Develops models to improve reasoning, truthfulness, and real-world capabilities.
Qualification
Experience training large models (e
Required
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
You believe truth-seeking AI is the most important and challenging problem
You are obsessed about building incredibly useful models through post-training and RL techniques
You are a power user of AI models and eager to push the boundaries of what’s possible with reinforcement learning and alignment methods
If you previously worked on post-training, RLHF, or trained models used by millions of people it’s a big plus, but relevant experience is not required
You take pride in your work and thrive in meritocratic environments
