Software Engineer (Post Training) - AI Model Development

Software Engineer (Post Training) - San Francisco, CA

A company building frontier-scale AI models that automate software engineering and AI research, combining ultra-long context, domain-specific RL, and massive compute infrastructure are looking for a Software Engineer (Post Training) to join their team.

What Will I Be Doing:

• Build and maintain robust, high-performance data pipelines to support large-scale post-training workflows
• Partner closely with research and applied teams to design strategies for sourcing diverse, targeted datasets at scale
• Develop creative approaches to generating high-quality synthetic data for model improvement
• Iterate on dataset filtering, scoring and quality heuristics to improve post-training outcomes
• Implement, test and operate data infrastructure supporting workloads from gigabytes to hundreds of petabytes

What We’re Looking For:

• Exceptional attention to detail and a strong commitment to data quality
• Ability to write reliable, well-tested production code
• Comfort learning new tools, languages and frameworks as needed
• End-to-end experience across data pipelines, from scraping and ingestion through processing and validation
• High intellectual agility, curiosity and grit to tackle complex, ambiguous problems

What’s In It for Me:

• Salary of $225K–$550K dependent on experience + significant equity
• Great benefits inc. 401(k) with 6% company match, comprehensive health, unlimited PTO
• Visa sponsorship and SF relocation stipend available
• Well-funded ($465M+) with backing from top investors

Apply now for immediate consideration!