Binary Cache Support
Up until now, nixbuild.net has not supported directly fetching build dependencies from binary caches like cache.nixos.org or Cachix. All build dependencies have instead been uploaded from the user’s local machine to nixbuild.net the first time they’ve been needed.
Today, this bottleneck has been removed, since nixbuild.net now can fetch build dependencies directly from binary caches, without taxing users’ upload bandwidth.
By default, the official Nix binary cache (cache.nixos.org) is added to all nixbuild.net accounts, but a nixbuild.net user can freely decide on which caches that should be queried for build dependencies (including Cachix caches).
An additional benefit of the new support for binary caches is that users that trust the same binary caches automatically share build dependencies from those caches. This means that if one user’s build has triggered a download from for example cache.nixos.org, the next user that comes along and needs the same build dependency doesn’t have to spend time on downloading that dependency.
For more information on how to use binary caches with nixbuild.net, see the documentation.