Add Nix derivation

nbackbright.nix

@@ -0,0 +1,24 @@
+{ pkgs ? import <nixpkgs> {} }:
+
+with pkgs;
+stdenv.mkDerivation rec {
+    pname = "nbackbright";
+    version = "0.1.0";
+    
+    src = fetchFromGitHub {
+        owner = "punzik";
+        repo  = "nbackbright";
+        rev = "558633c61da2a8cdcf2d46e38cdd44a5e43f09d1";
+        sha256 = "0756bw8qg608w67q4b5y27b3dbqv0dd2rflsdr3270avxwiybk41";
+    };
+
+    buildInputs = [ nim ];
+    buildPhase = ''
+        make
+    '';
+
+    installPhase = ''
+        mkdir -p $out/bin
+        mv nbackbright $out/bin
+    '';
+}