I added the new channel and updated. Trying to do a nixos-rebuild switch and get
# nixos-rebuild switch building Nix... building the system configuration... error: attribute 'library' missing at /nix/store/qwgw2b19ga8dr7c6wfpd6p87bdjyrnha-source/pkgs/development/libraries/libhwy/default.nix:30:14: 29| cmakeFlags = let 30| libExt = stdenv.hostPlatform.extensions.library; | ^ 31| in [ (use '--show-trace' to show detailed location information)
libhwy is clearly a dependency of something else.
I’m not even sure where to start troubleshooting.