misc: initial commit

nixos/user-system-config.nix

@@ -0,0 +1,54 @@
+# Configuration that really wants to be per-user,
+# but can't be defined from Home Manager.
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}: {
+  networking.firewall = lib.mkMerge [
+    # User-mode Syncthing
+    {
+      allowedTCPPorts = [22000];
+      allowedUDPPorts = [21027 22000];
+    }
+
+    # LocalSend
+    {allowedTCPPorts = [53317];}
+  ];
+
+  environment.systemPackages = lib.mkMerge [
+    [pkgs.ryujinx]
+    [
+      (pkgs.lutris.override {
+        extraLibraries = pkgs: [
+          pkgs.libvdpau
+          pkgs.openal
+          pkgs.speex
+          pkgs.libgudev
+        ];
+      })
+      pkgs.wineWowPackages.waylandFull
+    ]
+    # For gamemode status in GNOME
+    (lib.mkIf (config.services.xserver.desktopManager.gnome.enable) [
+      pkgs.gnomeExtensions.gamemode-indicator-in-system-settings
+    ])
+  ];
+
+  programs.steam = {
+    enable = true;
+    remotePlay.openFirewall = true;
+    gamescopeSession.enable = true;
+  };
+  programs.gamemode = {
+    enable = true;
+    enableRenice = true;
+    settings = {
+      general = {
+        softrealtime = "auto";
+        renice = 10;
+      };
+    };
+  };
+}