{
  lib,
  nixpkgs,
  module,
  pkgs,
  system,
}:

let
  uploadLimits = import ../upload-limits.nix;

  evaluatedConfig =
    (nixpkgs.lib.nixosSystem {
      inherit system;
      modules = [
        module
        {
          system.stateVersion = "26.05";

          services.rabbi-gerzi = {
            enable = true;
            frontend.hostName = "www.example.test";
            backend = {
              hostName = "api.example.test";
              environmentFile = "/run/secrets/rabbi-gerzi.env";
            };
          };
        }
      ];
    }).config;

  evaluatedHostName = evaluatedConfig.services.rabbi-gerzi.backend.hostName;

  backendVirtualHost = evaluatedConfig.services.nginx.virtualHosts.${evaluatedHostName};

  phpOptions = evaluatedConfig.services.phpfpm.pools.rabbi-gerzi.phpOptions;

  expectedUploadMaxFilesize = "upload_max_filesize = ${uploadLimits.phpUploadLimit}";

  expectedPostMaxSize = "post_max_size = ${uploadLimits.phpUploadLimit}";

  expectedNginxClientMaxBodySize = "client_max_body_size ${uploadLimits.nginxClientMaxBodySize};";

  assertions = [
    {
      passed = lib.hasInfix expectedUploadMaxFilesize phpOptions;
      message = "php-fpm upload_max_filesize is not 6M";
    }
    {
      passed = lib.hasInfix expectedPostMaxSize phpOptions;
      message = "php-fpm post_max_size is not 6M";
    }
    {
      passed = lib.hasInfix expectedNginxClientMaxBodySize backendVirtualHost.extraConfig;
      message = "nginx client_max_body_size is not 6m";
    }
  ];

  failedAssertions = lib.filter (assertion: !assertion.passed) assertions;
in
pkgs.runCommand "rabbi-gerzi-module-eval"
  {
    failures = lib.concatMapStringsSep "\n" (assertion: assertion.message) failedAssertions;
    value = evaluatedHostName;
    preferLocalBuild = true;
  }
  ''
    if [ -n "$failures" ]; then
      printf '%s\n' "$failures" >&2
      exit 1
    fi

    echo "$value" > $out
  ''