added nixpkgs-master

overlays/default.nix

@@ -6,4 +6,11 @@
       config.allowUnfree = true;
     };
   };
+  # When applied, the master nixpkgs set (declared in the flake inputs) will be accessible through 'pkgs.master'
+  master = final: _prev: {
+    master = import inputs.nixpkgs-master {
+      system = final.system;
+      config.allowUnfree = true;
+    };
+  };
 }