What Data from 20m Pull Requests Reveal About AI Transformation — Nick Arcolano, Jellyfish
Nov 24, 2025 · 17:57
Nick Arcolano, head of research at Jellyfish, presents data from 20 million pull requests across 200,000 engineers at 1,000 companies to reveal what AI transformation actually looks like. Median AI adoption of interactive coding tools (Copilot, Cursor, Claude Code) jumped from 22% in June 2024 to nearly 90% today, driving a 2x increase in PR throughput and 24% faster cycle times on average. Autonomous agents like Devin and Codex remain negligible—only 44% of companies have tried them, contributing less than 0.2% of PRs. PRs grow 18% larger with AI, but bug rates and reverts show no significant quality impact. Crucially, code architecture determines success: centralized and balanced repos see 4x throughput gains, while highly distributed architectures (many repos per engineer) show no correlation with AI adoption, likely due to cross-repo context limitations. Arcolano advises focusing on adoption first, then addressing architectural barriers to unlock productivity.
