diff --git a/README.md b/README.md
index 907a73a..75d7a73 100644
--- a/README.md
+++ b/README.md
@@ -58,8 +58,8 @@ Returns:
 ```nix
 {
   hello = «derivation»;
-  gitAndTools_git = «derivation»;
-  gitAndTools_hub = «derivation»;
+  "gitAndTools/git" = «derivation»;
+  "gitAndTools/hub" = «derivation»;
   # ...
 }
 ```
diff --git a/default.nix b/default.nix
index 978a2ad..d9eeb77 100644
--- a/default.nix
+++ b/default.nix
@@ -52,8 +52,8 @@ let
   #
   #   {
   #      hello = «derivation»;
-  #      gitAndTools_git = «derivation»;
-  #      gitAndTools_hub = «derivation»;
+  #      "gitAndTools/git" = «derivation»;
+  #      "gitAndTools/hub" = «derivation»;
   #      # ...
   #   }
   flattenTree = tree: import ./flattenTree.nix tree;
diff --git a/example/flake.nix b/example/flake.nix
index a3cc11b..28bd85f 100644
--- a/example/flake.nix
+++ b/example/flake.nix
@@ -7,7 +7,10 @@
     flake-utils.lib.eachDefaultSystem (system:
       let pkgs = nixpkgs.legacyPackages.${system}; in
       rec {
-        packages.hello = pkgs.hello;
+        packages = flake-utils.lib.flattenTree {
+          hello = pkgs.hello;
+          gitAndTools = pkgs.gitAndTools;
+        };
         defaultPackage = packages.hello;
         apps.hello = flake-utils.lib.mkApp { drv = packages.hello; };
         defaultApp = apps.hello;
diff --git a/flattenTree.nix b/flattenTree.nix
index a535f86..3ad30d0 100644
--- a/flattenTree.nix
+++ b/flattenTree.nix
@@ -2,7 +2,7 @@ tree:
 let
   op = sum: path: val:
     let
-      pathStr = builtins.concatStringsSep "_" path;
+      pathStr = builtins.concatStringsSep "/" path;
     in
     if (builtins.typeOf val) != "set" then
     # ignore that value