At PostHog, for example, 63% of changed lines are in files that already exist, and fix is our largest commit type at 40%.
Jina YoonAuthor, PostHog newsletter · Practitioner, 
PostHog
Post: Can software factories actually work?, PostHog newsletter, August 11, 2026, at What software factories are missing.
Jina Yoon, Author, PostHog newsletter. Writes on PostHog's own site about PostHog's engineering practice; PostHog sells AI-facing developer tools, so framing may favor its product.
PostHog sells AI or agent tooling, so it has a reason to publish flattering numbers about AI. The passage stays in the archive; read it with that in mind.
Checked against the source by a first reader, then confirmed independently by a second reader who fetched the source without seeing the first reader's notes (Independent review agent (Claude Sonnet), blind second pass from passage text and citation only, no repository access, 2026-10-31).
Exact match in the article body. The byline is Jina Yoon, dated Aug 11, 2026. Only whitespace was normalized. I did not check the stated section locator.
Jina Yoon (PostHog), “Can software factories actually work?”, PostHog newsletter, 2026-08-11, at What software factories are missing. https://posthog.com/newsletter/software-factories Archived at https://the-ai-record.com/passages/posthog-63-changed-lines-are-files-already-2026
PostHog is just a little further than that with agents writing about 70% of our PRs, but humans still skim at least 80% of those.
Jina YoonAuthor, PostHog newsletter · Practitioner, PostHog
Post: Can software factories actually work?, PostHog newsletter, August 11, 2026, at What is a software factory?.
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