diff --git a/pkgs/development/misc/bleeding-edge-repos/default.nix b/pkgs/development/misc/bleeding-edge-repos/default.nix
index 6a1121f48e2..079339efdbf 100644
--- a/pkgs/development/misc/bleeding-edge-repos/default.nix
+++ b/pkgs/development/misc/bleeding-edge-repos/default.nix
@@ -17,7 +17,7 @@ args:
           then (getAttr name fetchInfos) { inherit fetchurl; }
           else throw "no bleeding edge source attribute found in bleeding-edge-fetch-infos.nix with name ${name}\n"
                      "run NO_FETCH=1 nix-repository-manager <path to nixpkgs> --update <reponame> to add it automatically";
-        localTarGZ = managedRepoDir+"/dist/${ lib.dropPath (head fetchinfo.urls) }"; # hack, dropPath should be implemented as primop
+        localTarGZ = managedRepoDir+"/dist/${ builtins.baseNameOf (head fetchinfo.urls) }"; # hack, dropPath should be implemented as primop
         fetchInfos = import ../../../misc/bleeding-edge-fetch-infos.nix; in
     if (getConfig ["bleedingEdgeRepos" "useLocalRepos"] false && builtins.pathExists localTarGZ)
         then localTarGZ else fetchinfo;
diff --git a/pkgs/lib/strings.nix b/pkgs/lib/strings.nix
index ed8111b4e6a..e0271a3d20a 100644
--- a/pkgs/lib/strings.nix
+++ b/pkgs/lib/strings.nix
@@ -79,17 +79,6 @@ rec {
   # [] for zsh
   escapeShellArg = lib.escape (stringToCharacters "\\ ';$`()|<>\t*[]");
 
-  # arg: http://foo/bar/bz.ext returns bz.ext
-  # !!! isn't this what the `baseNameOf' primop does?
-  dropPath = s : 
-      if s == "" then "" else
-      let takeTillSlash = left : c : s :
-          if left == 0 then s
-          else if (substring left 1 s == "/") then
-                  (substring (add left 1) (sub c 1) s)
-          else takeTillSlash (sub left 1) (add c 1) s; in
-      takeTillSlash (sub (stringLength s) 1) 1 s;
-
   # Compares strings not requiring context equality
   # Obviously, a workaround but works on all Nix versions
   eqStrings = a: b: (a+(substring 0 0 b)) == ((substring 0 0 a)+b);