error:
       … while calling the 'derivationStrict' builtin
         at «nix-internal»/derivation-internal.nix:37:12:
           36|
           37|   strict = derivationStrict drvAttrs;
             |            ^
           38|

       … while evaluating derivation 'nixos-system-marvin-26.11.19800101.a5cbcfe'
         whose name attribute is located at «https://releases.nixos.org/nixpkgs/nixpkgs-26.11pre1045908.a5cbcfe95479/nixexprs.tar.zst?narHash=sha256-Kr66C7mAWVoVLl2vhGoDaDksNBHRIHneLaO2/c4drCw%3D»/pkgs/stdenv/generic/make-derivation.nix:651:11

       … while evaluating attribute 'buildCommand' of derivation 'nixos-system-marvin-26.11.19800101.a5cbcfe'
         at «https://releases.nixos.org/nixpkgs/nixpkgs-26.11pre1045908.a5cbcfe95479/nixexprs.tar.zst?narHash=sha256-Kr66C7mAWVoVLl2vhGoDaDksNBHRIHneLaO2/c4drCw%3D»/nixos/modules/system/activation/top-level.nix:63:7:
           62|       allowSubstitutes = false;
           63|       buildCommand = systemBuilder;
             |       ^
           64|

       … while evaluating the option `environment.etc."systemd/system".source':

       … while evaluating the option `systemd.units."paperless-web.service".text':

       … while evaluating definitions from `/nix/store/p6wbvbf52ridpawj7wlyi8j2f3zpy3s2-source/nixos/modules/system/boot/systemd.nix':

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

       error: The option `systemd.services.paperless-web.serviceConfig.ExecStart' has conflicting definition values:
       - In `/nix/store/p6wbvbf52ridpawj7wlyi8j2f3zpy3s2-source/nixos/modules/system/boot/systemd.nix': "/nix/store/lrpr68v18r32k9kp8c84lznnlyqjgb23-unit-script-paperless-web-start/bin/paperless-web-start "
       - In `/nix/store/p6wbvbf52ridpawj7wlyi8j2f3zpy3s2-source/nixos/modules/services/misc/paperless.nix': "/nix/store/rl4x6b698xfzh478fmg1avb34nihmjr2-python3.14-granian-2.7.9/bin/granian --interface asginl --ws paperless.asgi:application"
       Use `lib.mkForce value` or `lib.mkDefault value` to change the priority on any of these definitions.