Software Engineer, Pretraining Data (AI)

Location: Onsite in Palo Alto, California; must be able to work in person at the Palo Alto office.

Annual salary: $160,000–$250,000 USD. Base salary varies by level, knowledge, skills, education, and experience.

Company

Cursor AI is building AI products and a full superintelligence stack, including large-scale compute, frontier models, and applications.

What you will do

• Build data platforms that transform raw web, code, multimodal, and acquired data into training-ready datasets for frontier pretraining.
• Own scalable pipelines, orchestration, tooling, observability, lineage, freshness, and reproducibility for pretraining data iteration.
• Build high-throughput, fully telemetered systems and models that classify, rank, filter, clean, and identify data.
• Design scaling-ladder experiments covering data mixtures, repeatability, and quality depth, connecting data changes to loss, evaluations, and model capability.
• Build and scale web crawlers for URL discovery, scheduling, fetching, parsing, host scoring, fair scheduling, and improved coverage.
• Partner with initial training, crawling, data quality, data platform, and acquisition teams to improve training data and resolve infrastructure issues.

Requirements

• At least 3 years of software engineering experience.
• Experience building distributed systems and/or large-scale data infrastructure.
• Ability to architect and ship end-to-end with high ownership and debug complex systems independently.
• Strong intuitions about large-scale distributed systems.
• Ability to work alongside AI agents.
• Must be able to work onsite at the Palo Alto office.

Nice to have

• High-slope engineering background with unusually rapid progression, such as staff-level ownership within a few years, or relevant domain experience.
• Interest in how pretraining data shapes model quality and in owning systems that feed frontier training runs.

Culture & Benefits

• Full-time onsite work with close collaboration across data, crawling, acquisition, and training teams.
• Equity and comprehensive medical, vision, and dental coverage.
• Access to a 401(k) retirement plan.
• Short- and long-term disability insurance, life insurance, discounts, and other perks.