Add failing nixoModule

nix/nixos-configs.nix

@@ -1,6 +1,5 @@
 { repoRoot, inputs }:
 {
-  nixosConfigurations = {
     hydra-explorer = inputs.nixpkgs.lib.nixosSystem {
       system = "x86_64-linux";
       specialArgs = inputs;
@@ -18,6 +17,7 @@
           imports = [
             "${inputs.nixpkgs}/nixos/modules/virtualisation/amazon-image.nix"
             inputs.cardano-node.nixosModules.cardano-node
+            (import (inputs.self + "/nix/nixosModule.nix") { inherit inputs; })
           ];
 
           networking = {
@@ -36,11 +36,12 @@
             port = 3002;
           };
 
+          services.hydra-explorer.enable = true;
+
           services.openssh.enable = true;
 
           system.stateVersion = "24.05";
         }
       ];
     };
-  };
-}
+}

nix/nixosModule.nix

@@ -0,0 +1,75 @@
+{ inputs, ... }:
+{ config, pkgs, lib, ... }:
+
+let cfg = config.services.hydra-explorer;
+
+in
+
+with lib;
+
+{
+  options = {
+    services.hydra-explorer = {
+      enable = mkOption {
+        default = false;
+        type = types.bool;
+        description = ''
+          Enable hydra-explorer
+        '';
+      };
+      package = mkOption {
+        type = types.package;
+        default = inputs.self.packages.x86_64-linux.hydra-explorer;
+        description = ''
+          The hydra-explorer package to use.
+        '';
+      };
+      socketPath = mkOption {
+        type = types.path;
+        default = config.services.cardano-node.socketPath;
+        description = ''
+          The node socket
+        '';
+      };
+      port = mkOption {
+        type = types.port;
+        default = 9081;
+        description = ''
+          The port to run on
+        '';
+      };
+      user = mkOption {
+        type = types.str;
+        default = config.services.cardano-node.user;
+        description = ''
+          The user to run the systemd service
+        '';
+      };
+      group = mkOption {
+        type = types.str;
+        default = config.services.cardano-node.group;
+        description = ''
+          The group to run the systemd service.
+        '';
+      };
+    };
+  };
+
+  config = mkIf cfg.enable {
+    systemd.services.hydra-explorer = {
+      after = [ "cardano-node.service" ];
+      enable = true;
+      description = "Hydra Explorer";
+      unitConfig = {
+        Type = "simple";
+      };
+      serviceConfig = {
+        ExecStart = "${cfg.package}/bin/hydra-explorer --node-socket ${cfg.socketPath} --port ${toString cfg.port}";
+        Restart = "on-failure";
+        User = cfg.user;
+        Group = cfg.group;
+      };
+      wantedBy = [ "multi-user.target" ];
+    };
+  };
+}