nixos/envision: init module

nixos/modules/module-list.nix

@@ -181,6 +181,7 @@
   ./programs/dublin-traceroute.nix
   ./programs/ecryptfs.nix
   ./programs/environment.nix
+  ./programs/envision.nix
   ./programs/evince.nix
   ./programs/extra-container.nix
   ./programs/fcast-receiver.nix

nixos/modules/programs/envision.nix

@@ -0,0 +1,43 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+
+let
+  cfg = config.programs.envision;
+in
+{
+
+  options = {
+    programs.envision = {
+      enable = lib.mkEnableOption "envision";
+
+      package = lib.mkPackageOption pkgs "envision" {};
+
+      openFirewall = lib.mkEnableOption "the default ports in the firewall for the WiVRn server" // {
+        default = true;
+      };
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    services.avahi = {
+      enable = true;
+      publish = {
+        enable = true;
+        userServices = true;
+      };
+    };
+
+    environment.systemPackages = [ cfg.package ];
+
+    networking.firewall = lib.mkIf cfg.openFirewall {
+      allowedTCPPorts = [ 9757 ];
+      allowedUDPPorts = [ 9757 ];
+    };
+  };
+
+  meta.maintainers = pkgs.envision.meta.maintainers;
+}