add gps-share and relevant config

nixos/hosts/trailblazer/default.nix

@@ -221,6 +221,20 @@ in
     script = "${commandScript}/bin/trailblazer-command-daemon";
   };
 
+  #
+  # Let trailblazer share its GPS with the house devices.
+  #
+  systemd.services.gps-share = {
+    description = "share our GPS with our other devices on the LAN";
+
+    # Start once we're online.
+    wantedBy = [ "default.target" ];
+    wants = [ "network-online.target" ];
+    after = [ "network-online.target" ];
+
+    script = "${deprekages.gps-share}/bin/gps-share /dev/ttyACM0";
+  };
+
   #
   # Hardware config.
   #

packages/default.nix

@@ -95,6 +95,7 @@ flake-utils.lib.eachDefaultSystem (
       # hw support
       dell = callPackage ./dell { };
       synatudor = callPackage ./synatudor { };
+      gps-share = callPackage ./gps-share.nix { };
 
       # udev rules~
       t5-udev-rules = callPackage ./t5-udev-rules { };

packages/gps-share.nix

@@ -0,0 +1,29 @@
+#
+# Wayland-satellite Xwayland implementation.
+#
+# vim: et:ts=2:sw=2:
+{
+  rustPlatform,
+  fetchFromGitHub,
+  udev,
+  pkg-config,
+}:
+rustPlatform.buildRustPackage rec {
+  pname = "gps-share";
+  version = "0.3.1";
+
+  src = fetchFromGitHub {
+    owner = "zeenix";
+    repo = pname;
+    rev = "${version}";
+    hash = "sha256-Rh7Pt9JN30TyuxwHOn8dwZrUfmkknUhOGonbhROpGxA=";
+  };
+
+  cargoHash = "sha256-WhYHFaSZfnlEmlXFLj7BIt0agMFuz07LcAXJ9ZOOrvY=";
+
+  buildInputs = [ udev ];
+  nativeBuildInputs = [ pkg-config ];
+
+  # Checks require a live device, so we'll skip them.
+  doCheck = false;
+}