Research Engineer, Production Model Post-Training

About the Role

Anthropic's production models undergo sophisticated post-training processes to enhance their capabilities, alignment, and safety. As a Research Engineer on our Post-Training team, you'll train base models through the complete post-training stack to deliver production Claude models.

You will work 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.

*Note: All interviews are conducted in Python. This role may require responding to incidents on short notice, including on weekends.*

Responsibilities

• 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

Qualifications

• Proficiency in Python, deep learning frameworks, and distributed computing (required)
• Strong software engineering skills with experience building complex ML systems
• Comfort working with large-scale distributed systems and high-performance computing
• Experience training, fine-tuning, or evaluating large language models
• Ability to balance research exploration with engineering rigor and operational reliability
• Skilled at analyzing and debugging model training processes and complex, time-sensitive issues
• Comfort navigating ambiguity, changing priorities, and fast-moving research environments

Bonus Qualifications

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