error:
       … while evaluating a branch condition
         at «string»:23:10:
           22|     if !keepName n then {}
           23|     else if !builtins.isAttrs c || isDrv c then c
             |          ^
           24|     else if c ? _type || !(c.recurseForDerivations or true) then {}

       … in the left operand of the OR (||) operator
         at «string»:23:33:
           22|     if !keepName n then {}
           23|     else if !builtins.isAttrs c || isDrv c then c
             |                                 ^
           24|     else if c ? _type || !(c.recurseForDerivations or true) then {}

       … while evaluating definitions from `/nix/store/xfg4bws749i95jvnxhymxmfwailzk38q-source/modules/transposition.nix':

       … while evaluating definitions from `/nix/store/8wvvw4mp736anf4k2vbh8xnblf6124g6-source/modules/flake-parts/treefmt.nix, via option perSystem':

       … while evaluating the option `system.build.toplevel':

       … while evaluating definitions from `/nix/store/7j1q60m17gf95k3s0gk2qvjqygnp1q36-source/nixos/modules/system/activation/top-level.nix':

       … while evaluating the option `assertions':

       … while evaluating definitions from `/nix/store/k3hjawq2nmfd322gi049r531zj3x2r68-source/nixos/common.nix':

       … while evaluating the option `home-manager.users.simon.assertions':

       … while evaluating definitions from `/nix/store/k3hjawq2nmfd322gi049r531zj3x2r68-source/modules/services/window-managers/niri.nix':

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

       error: The option `home-manager.users.simon.wayland.windowManager.niri.enable' in `/nix/store/k3hjawq2nmfd322gi049r531zj3x2r68-source/modules/services/window-managers/niri.nix' is already declared in `/nix/store/gr7ix223fj1ydfvrv6y39fi8995m7qhz-source/modules/home.nix'.