Importing a channel is broken now?

Help
1

I used to be able to import a channel in my configuration.nix, so I could get unstable packages while my nixos is on stable, or vice versa. Is that broken now? Or maybe they are phasing channels out?

on my stable machine:

[bburdette@HOSS:~]$ sudo nix-channel --list
[sudo] password for bburdette:
nixos https://nixos.org/channels/nixos-22.11
nixos-22.11 https://nixos.org/channels/nixos-22.11
nixos-unstable https://nixos.org/channels/nixos-unstable

[bburdette@HOSS:~]$ sudo nix repl
Welcome to Nix 2.11.1. Type :? for help.

nix-repl> <nixos-22.11>
/nix/var/nix/profiles/per-user/root/channels/nixos-22.11

on a machine running unstable:

bburdette@BB-5520:~$ sudo nix-channel --list
nixos https://nixos.org/channels/nixos-unstable
nixos-22-11 https://nixos.org/channels/nixos-22.11
nixosstable https://nixos.org/channels/nixos-22.11
bburdette@BB-5520:~$ sudo nix repl
Welcome to Nix 2.14.1. Type :? for help.

nix-repl> <nixos-22-11>
error:
       … while calling the 'findFile' builtin

         at «string»:1:1:

            1| <nixos-22-11>
             | ^

       error: file 'nixos-22-11' was not found in the Nix search path (add it using $NIX_PATH or -I)

       at «none»:0: (source not available)

nix-repl>
2

You probably changed NIX_PATH somehow. The default still includes root’s channels.

3

interesting… for root it looks the same to me, except on my laptop its different in my user account.

on my machine with 22.11:

[bburdette@HOSS:~]$ echo $NIX_PATH
nixpkgs=/nix/var/nix/profiles/per-user/root/channels/nixos:nixos-config=/etc/nixos/configuration.nix:/nix/var/nix/profiles/per-user/root/channels
[bburdette@HOSS:~]$ su
Password:

[root@HOSS:/home/bburdette]# echo $NIX_PATH
nixpkgs=/nix/var/nix/profiles/per-user/root/channels/nixos:nixos-config=/etc/nixos/configuration.nix:/nix/var/nix/profiles/per-user/root/channels

And on my hapless laptop:

[bburdette@BB-5520:~]$ echo $NIX_PATH
home/bburdette/.nix-defexpr/channels:nixpkgs=/nix/var/nix/profiles/per-user/root/channels/nixos:nixos-config=/etc/nixos/configuration.nix:/nix/var/nix/profiles/per-user/root/channels
bburdette@BB-5520:~$ su
Password:

[root@BB-5520:/home/bburdette]# echo $NIX_PATH
nixpkgs=/nix/var/nix/profiles/per-user/root/channels/nixos:nixos-config=/etc/nixos/configuration.nix:/nix/var/nix/profiles/per-user/root/channels

TLDR: same paths in root, but in user there’s the .nix-defexpr bit on the laptop.