Include flake.nix file

flake.nix

@@ -0,0 +1,40 @@
+{
+  description = "GTK4 Minesweeper game";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.05";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = { self, nixpkgs, flake-utils }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = import nixpkgs { inherit system; };
+      in {
+
+        # Main package
+        packages.default = pkgs.stdenv.mkDerivation rec {
+          pname = "minesweeper";
+          version = "0.1";
+
+          src = self;
+
+          nativeBuildInputs = [ pkgs.meson pkgs.ninja pkgs.pkg-config ];
+          buildInputs = [ pkgs.gtkmm4 pkgs.libsigcxx30 pkgs.glibmm ];
+
+          meta = with pkgs.lib; {
+            description = "A simple GTKmm4 Minesweeper game";
+            homepage = "https://example.org/minesweeper";
+            license = licenses.gpl3Plus;
+            platforms = platforms.linux;
+          };
+        };
+
+        # Dev shell for hacking
+        devShells.default = pkgs.mkShell {
+          nativeBuildInputs = [ pkgs.meson pkgs.ninja pkgs.pkg-config ];
+          buildInputs = [ pkgs.gtkmm4 pkgs.libsigcxx30 pkgs.glibmm ];
+        };
+
+      });
+}