Research Engineer, Post-Training

Job title: Research Engineer, Post-Training

About the Role Anthropic's production models undergo sophisticated post-training processes to enhance capabilities, alignment, and safety. As a Research Engineer on the Post-Training team, you'll train base models through the complete post-training stack to deliver production Claude models that users interact with. This role sits at the intersection of cutting-edge research and production engineering, implementing, scaling, and improving post-training techniques like Constitutional AI, RLHF, and other alignment methodologies.

What You'll Do

• Implement and optimize post-training techniques at scale on frontier models
• Conduct research to develop and optimize post-training recipes that directly improve production model quality
• Design, build, and run robust, efficient pipelines for model fine-tuning and evaluation
• Develop tools to measure and improve model performance across various dimensions
• Collaborate with research teams to translate emerging techniques into production-ready implementations
• Debug complex issues in training pipelines and model behavior
• Help establish best practices for reliable, reproducible model post-training

What We're Looking For

• Thrive in controlled chaos and are energised, rather than overwhelmed, when juggling multiple urgent priorities
• Adapt quickly to changing priorities
• Maintain clarity when debugging complex, time-sensitive issues
• Have strong software engineering skills with experience building complex ML systems
• Are comfortable working with large-scale distributed systems and high-performance computing
• Have experience with training, fine-tuning, or evaluating large language models
• Can balance research exploration with engineering rigor and operational reliability
• Are adept at analyzing and debugging model training processes
• Enjoy collaborating across research and engineering disciplines
• Can navigate ambiguity and make progress in fast-moving research environments
• Strong candidates may also:
• Have experience with LLMs
• Have a keen interest in AI safety and responsible deployment

Nice to Have

• Experience with LLMs
• Keen interest in AI safety and responsible deployment

Compensation & Benefits

• Salary and benefits not disclosed.