[Nix-dev] 6 month C4 adoption period

[stewart mackenzie]

I just want this issue resolved.

Every time I update / upgrade I recompile rustBeta then rustUnstable
and it results in 1/2 day lost. This has happened frequently, recently
as rustUnstable and rustBeta have been broken for a long time.
(ie days have been lost finding working revs then compiling rust)

If the lowprio removal doesn't solve this then how can I get it such
that when I issue a `nixos-rebuild --upgrade switch` and my
configuration.nix contains `rustUnstable.rustc`  downloads these
binaries http://hydra.nixos.org/job/nixos/release-16.03/nixpkgs.rustUnstable.rustc.x86_64-linux.

What exactly does lowprio do?