error:
       … while evaluating a branch condition
         at «string»:25:5:
           24|     v:
           25|     if !builtins.isAttrs v || isDrv v then
             |     ^
           26|       v

       … in the left operand of the OR (||) operator
         at «string»:25:28:
           24|     v:
           25|     if !builtins.isAttrs v || isDrv v then
             |                            ^
           26|       v

       … while evaluating definitions from `/nix/store/9iv83r72z5xwgylkwms1qip1ijnr6jqs-source/modules/transposition.nix':

       … while evaluating the option `perSystem.x86_64-linux.checks':

       … while evaluating definitions from `/nix/store/41i1m3r4p5c3y8lbc9wh4k2f0za98vkn-source/flake.nix, via option perSystem':

       (stack trace truncated; use '--show-trace' to show the full, detailed trace)

       error: Failed to fetch git repository 'https://git.sr.ht/~watersucks/optnix'