diff --git a/lib/default.nix b/lib/default.nix
index db0c21d..55efd46 100644
--- a/lib/default.nix
+++ b/lib/default.nix
@@ -27,6 +27,11 @@ rec {
     replaceStrings
       [ "." ] [ "" ]
       (sanitizeDerivationName (removePrefix "/" name));
+
+  mapGenAttrs = list: func: attrs:
+    lib.genAttrs list (name: func (if builtins.typeOf attrs == "lambda" then attrs name else attrs));
+
+  dirsOf = dir: lib.attrNames (lib.filterAttrs (file: type: type == "directory") (builtins.readDir dir));
 } // (
   import ./digga.nix { inherit lib; }
 ) // (