There now seems to be a nixos-19.03 channel, which I thought was for beta testing. It was created 6 days ago but does not seem to be updated when its builds are successful.
Was its creation premature, or is there some automatic update issue with the 19.03beta labeling?
Hmm, I can’t see anything holding the updates. There might be an issue; occasionally we had some not visible on Hydra.nixos.org.
In any case, channel updating slower doesn’t seem to matter much in this beta phase. There are binaries regardless, so you may e.g. follow git if you want it faster.
In this case the problem was Hydra’s job for 19.03 was first created as “stable” and then updated to be marked as beta. This tripped the channel updates “is this going backwards?” check:
channel would go back in time from nixos-19.03.170684.07e2b59812d to nixos-19.03beta170789.58e31b2692
I forced two channel bumps for 19.03 and 19.03-small, and this problem should be fixed.
Thanks.
Concerning following Git, I am not sure what you had in mind. It was straight forward getting the full git revision of the last successful build from Hydra, and doing:
nix-channel --add https://github.com/NixOS/nixpkgs/archive/${REV}.tar.gz nixos
The NixOS manuals only seem to deal with using the standard channels, as far as I have been able to tell.
I meant hand-managing the source, e.g.:
$ git clone https://github.com/NixOS/nixpkgs -b release-19.03 --depth 1
$ nixos-rebuild build -I nixpkgs=./nixpkgs
You still get binary caches, etc. There are also branches in GitHub - NixOS/nixpkgs-channels: DEPRECATED! Use NixOS/nixpkgs repository instead. that follow the channel revisions, if you want that information.
EDIT: it’s also possible to use
$ nixos-rebuild build -I nixpkgs=https://github.com/NixOS/nixpkgs/archive/release-19.03.tar.gz