AfterQuery · San Francisco
Data & AIEngineeringFullTimeposted 8w ago
AfterQuery is an applied research lab curating data solutions for foundation model development. We serve every frontier AI lab with the mission of delivering the best data to power the best models. In doing so, we can make expertise that once took a lifetime to build available to anyone who needs it.
Our customers are the ones building the foundation models themselves and our work sits directly in the loop of how those systems improve. This is a rare opportunity to join a company at a defining moment in AI. We are YC's fastest unicorn, valued at $3.2 billion. We're based in San Francisco and backed by leading investors including Altos Ventures, BoxGroup, and Y Combinator and angels from Google DeepMind, OpenAI, Anthropic, Meta Superintelligence Labs, and Microsoft AI.
Massive Opportunity: We are YC's fastest unicorn valued at $3.2 billion and we're not slowing down.
Founding Impact: You will own and architect core infrastructure systems that power our platform from the ground up.
Equity & Growth: Competitive salary and meaningful equity. As we scale, you’ll have the opportunity to shape the engineering organization and lead major technical initiatives.
Strong Team: Our founding team has experience from Citadel Securities, Meta, Google, Silver Lake, and Morgan Stanley — work alongside world-class engineers and researchers.
We’re hiring a Founding Machine Learning Engineer, Quality Intelligence to build the ML systems behind how we measure, improve, and scale data quality. You’ll work on production systems at the intersection of machine learning, human expertise, and frontier model evaluation.
This role is for someone who wants to build practical ML systems that directly improve the quality, reliability, and scalability of expert human data.
Build ML and data systems that help measure quality across complex human data workflows
Develop systems for expert matching, quality prediction, and anomaly detection
Build evaluation infrastructure for tasks, reviewers, projects, and data deliveries
Turn messy real-world signals into models, metrics, and product improvements
Partner with engineers, domain experts, and operators to improve how high-quality data is created and reviewed
Own high-impact systems from early design through production deployment
3-6 YOE with relevant experiences
Strong software engineering background with experience shipping production systems
Experience with applied ML, ranking, recommendations, search quality, marketplace systems, trust/safety, fraud, or data quality systems
Strong data intuition and ability to work with messy, ambiguous real-world signals
Comfort working across backend systems, data pipelines, ML models, and internal tools
Ability to move quickly in a high-ownership, fast-changing environment
Deep care for quality, precision, and customer impact
Health Insurance: Medical, Vision, Dental
401(k) with Employer Match
Daily Meals: Daily UberEats Stipend
Monthly Wellness Stipend
Commute Covered
We are an equal opportunity employer committed to providing a workplace free from discrimination and harassment. Employment decisions are made without regard to legally protected characteristics under applicable federal, state, or local law.
We comply with applicable pay transparency requirements and provide compensation ranges based on the position, qualifications, experience, and other relevant factors. Reasonable accommodations are available to qualified individuals with disabilities and for sincerely held religious beliefs, as required by law. This job description is intended to describe the general nature and level of work performed and is not an exhaustive list of all duties, responsibilities, qualifications, or working conditions associated with the position. We reserve the right to modify this job description as business needs change.