How we know
We took the full public history of each project and kept the changes written between 7 October 2025 and 7 October 2026, leaving out merges and bots. A person counts if they made ten or more changes in that time. A change's author is not always the maintainer, and some of these projects publish their history as a copy of another system.
For devices we counted a project on a platform only when we could see it there. On Android we listed the system libraries of an Android 16 image and read inside them, which is how we found that Android's "liblzma" is 7-Zip's code and not xz. For the iPhone we read the system libraries listed in Apple's iOS 26.2 developer kit. For Windows we used Microsoft's announcement for curl and the code inside Edge, which comes with every copy. Android has over three billion active devices (Google, 2022), iPhones over one billion (Apple, 2021) and Windows 1.6 billion a month (Microsoft, 2026). Macs, iPads, servers, cars and TVs are left out, so every device number here is lower than the real one.
"No public grant" means none from the Sovereign Tech Agency, Alpha-Omega, Open Collective or GitHub Sponsors, not that nobody has ever paid these people. If we got your project wrong, tell us and we will fix it.
Data: the 23-project table · every change shown · time zone lines with who last changed them · the script.
Sources: tz mailing list and RFC 6557; IANA tzdb NEWS 2026e; EFF, Astrolabe v. Olson; xz-devel, 8 June 2022; Russ Cox's xz timeline; Andres Freund on oss-security, 29 March 2024; Denis Pushkarev, "So, what's next?" (2023); millert.dev and The Register, 3 February 2026; libjpeg-turbo.org; sqlite.org/mostdeployed and /crew; Wikipedia on Mark Adler; David A. Wheeler's Shellshock timeline; HarfBuzz README; daniel.haxx.se, 2025 review; Steve Marquess, "Of Money, Responsibility, and Pride" (2014); Netcraft, 7 April 2014; sovereign.tech; Alpha-Omega 2025 report; GNOME Discourse, 15 September 2025; pgsql-hackers, 17 December 2025.
Photos: Paul Eggert, FSF / LibrePlanet 2022, CC BY-SA 3.0. Mark Adler, NASA, public domain. Behdad Esfahbod, CC0. Daniel Stenberg, CC BY 4.0. Comic: xkcd 2347, CC BY-NC 2.5.