Adoption is broad. Many contributors are committing agent-authored work, which is what a real organisational rollout looks like.
Assisted or autonomous
Assisted — a developer’s identity authored the commit and the agent added itself as co-author. The agent ran git commit during a working session, with a person there. Autonomous — a bot identity is the author, no human in the loop. Across the whole index, 93.7% of agent commits are assisted.
Agent share by month
Peak month: 9.6%. Bars are scaled to that peak, not to 100%.
Which agents
| Claude Code | Anthropic | 43 | 2.9% |
| Cursor Agent | Anysphere | 1 | 0.1% |
| GitHub Copilot | GitHub | 1 | 0.1% |
Verify it yourself
Sample commits that matched. Every one links to GitHub — check the trailers.
f91c1e35Speed up TimeWithZone#xmlschema, #to_s and TimeZone.seconds_to_utc_offsetClaude Code3c750994Fix keepalive: false being ignored in database.ymlClaude Code4c803f0fBound background-maintenance checkout wait to checkout_timeoutClaude Code4cb62a67Fix Encoding::CompatibilityError in template digests.Cursor Agent61f9d51bFix SafeBuffer MessagePack encoding round-tripGitHub Copilot
What was excluded
| Commits in window | 2,619 |
| Merge commits removed | −1,131 |
| CI / dependency bots removed | −0 |
| Considered | 1,488 |
Bots are excluded from the denominator entirely. Counting dependabot as “AI-written code” is the fastest way to produce a meaningless number.
How this was measured
Measured over February–August 2026, cloned directly. Detection is deterministic string matching against signatures agents write about themselves — no heuristics, no style analysis. Merge commits and CI bots are excluded from the denominator. The figure is a floor: squash merges strip trailers, so real usage is higher. Contributor counts are aggregate — no individual is named.
Run it yourself: npx qmmit-cli rails/rails