Package for nix

Signed-off-by: Slendi <slendi@socopon.com>

flake.nix

@@ -48,18 +48,48 @@
           inherit system;
           overlays = [ overlay ];
         };
+
+        commonBuildInputs = with pkgs; [
+          openssl
+        ];
+
+        commonNativeBuildInputs = with pkgs; [
+          pkg-config
+        ];
+
+        singerPackage = pkgs.rustPlatform.buildRustPackage {
+          pname = "singer";
+          version = "0.1.0";
+
+          src = pkgs.lib.cleanSource ./.;
+
+          cargoLock.lockFile = ./Cargo.lock;
+
+          nativeBuildInputs = commonNativeBuildInputs;
+          buildInputs = commonBuildInputs;
+        };
       in
       {
+        packages = {
+          singer = singerPackage;
+          default = singerPackage;
+        };
+
+        apps.default = {
+          type = "app";
+          program = "${singerPackage}/bin/singer";
+        };
+
         devShells.default = pkgs.mkShell {
-          packages = with pkgs; [
+          packages = (with pkgs; [
               rustToolchain
-            openssl
-            pkg-config
               cargo-deny
               cargo-edit
               cargo-watch
               rust-analyzer
-          ];
+            ])
+            ++ commonBuildInputs
+            ++ commonNativeBuildInputs;
 
           shellHook = ''
             export RUST_SRC_PATH="${pkgs.rustToolchain}/lib/rustlib/src/rust/library"