name: tarball-ttl internalName: tarballTtl type: unsigned int default: 3600 # 60 * 60

The number of seconds a downloaded tarball is considered fresh. If the cached tarball is stale, Lix will check whether it is still up to date using the ETag header. Lix will download a new version if the ETag header is unsupported, or the cached ETag doesn't match.

Setting the TTL to 0 forces Lix to always check if the tarball is up to date.

Lix caches tarballs in $XDG_CACHE_HOME/nix/tarballs.

Files fetched via NIX_PATH, fetchGit, fetchMercurial, fetchTarball, and fetchurl respect this TTL.