> Most open source software packages are also compiled for BSD variants, they switched to 64 bit time_t a long time ago and reported back upstream any problems.

* NetBSD in 2012: https://www.netbsd.org/releases/formal-6/NetBSD-6.0.html

* OpenBSD in 2014: http://www.openbsd.org/55.html

For packaging, NetBSD uses their (multi-platform) Pkgsrc, which has 29,000 packages, which probably covers a large swath of open source stuff:

* https://pkgsrc.org

On FreeBSD, the last platform to move to 64-bit time_t was powerpc in 2017:

* https://lists.freebsd.org/pipermail/svn-src-all/2017-June/14...

but amd64 was in 2012:

* https://github.com/freebsd/freebsd-src/commit/8f77be2b4ce5e3...

with only i386 remaining:

* https://man.freebsd.org/cgi/man.cgi?query=arch

* https://github.com/freebsd/freebsd-src/blob/main/share/man/m...