add(syncthing): add module for syncthing with basic configuration

modules/nixos/services/syncthing/default.nix

@@ -0,0 +1,44 @@
+{
+  lib,
+  pkgs,
+  config,
+  namespace,
+  ...
+}:
+with lib;
+with lib.${namespace};
+let
+  cfg = config.${namespace}.services.syncthing;
+in
+{
+  options.${namespace}.services.syncthing = {
+    enable = mkEnableOption "Syncthing";
+
+    port = mkOption {
+      description = "The port to serve Syncthing on.";
+      type = types.nullOr types.int;
+      default = 8384;
+    };
+
+    ip = mkOption {
+      description = "The ip to serve Syncthing on.";
+      type = types.nullOr types.str;
+      default = "192.168.10.3";
+    };
+
+    openDefaultPorts = mkEnableOption "Whether to open the default ports in the firewall.";
+
+  };
+  config = mkIf cfg.enable {
+    networking.firewall.allowedTCPPorts = [
+      cfg.port
+    ];
+
+    services.syncthing = {
+      enable = true;
+      guiAddress = "${cfg.ip}:${toString cfg.port}";
+      openDefaultPorts = mkIf cfg.openDefaultPorts true;
+      dataDir = "/data/syncthing";
+    };
+  };
+}

systems/x86_64-linux/blarm/default.nix

@@ -61,6 +61,7 @@ with lib.${namespace};
       searxng = enabled;
       #immich = enabled; # We wait for the proper version to be in nixpkgs
       paperless = enabled;
+      syncthing = enabled;
     };
 
     #container.invidious = enabled;