New offer - be the first one to apply!
July 14, 2026
Member of Technical Staff - Post-Training and RL
Mid • On-site
180,000 - 600,000 USD/yr
Palo Alto, CA
SpaceXAI's mission is to create AI systems that can accurately understand the universe and aid humanity in its pursuit of knowledge. The team is small, highly motivated, and focused on engineering excellence. Employees are expected to be hands-on, contribute directly to the mission, show initiative, and communicate clearly with teammates.
About the Role
You will work on critical post-training and reinforcement learning challenges, including reward modeling, preference optimization (RLHF/DPO), and reinforcement learning for improving reasoning, truthfulness, and real-world capabilities.
You will get clarity on your first project before an offer.
Basic Qualifications
- Believe truth-seeking AI is an important and challenging problem
- Passion for building useful models through post-training and RL techniques
- Strong interest in reinforcement learning and alignment methods
- Experience with post-training, RLHF, or large-scale model training is a plus
- Strong work ethic and prioritization skills
- Strong communication skills
- Ability to thrive in meritocratic environments
Compensation and Benefits
- $180,000 - $600,000 USD
- Equity package
- Medical, vision, and dental coverage
- 401(k) retirement plan
- Short and long-term disability insurance
- Life insurance
- Additional discounts and perks
SpaceXAI is an equal opportunity employer.
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