Version archive

Every release ever published, on every channel. Older versions stay available indefinitely: a paper that names a version should still be reproducible years later.

Retention

Nothing is removed. If a release turns out to be harmful it is marked as such rather than deleted, because someone may have cited it and a citation that resolves to nothing is worse than one that resolves to a warning.

Nightly builds are the exception: they are kept for ninety days. There is no reason to reproduce an unreviewed build from last year, and keeping every one of them forever would drown the archive.