1 files changed, 1 insertions, 2 deletions
diff --git a/pkgs/applications/science/logic/prooftree/default.nix b/pkgs/applications/science/logic/prooftree/default.nix
index adb64f02c14f8..d0d95818ff93b 100644
--- a/pkgs/applications/science/logic/prooftree/default.nix
+++ b/pkgs/applications/science/logic/prooftree/default.nix
@@ -14,8 +14,7 @@ stdenv.mkDerivation rec {
   nativeBuildInputs = [ pkg-config ] ++ (with ocamlPackages; [ ocaml findlib camlp5 ]);
   buildInputs = [ ncurses ] ++ (with ocamlPackages; [ lablgtk ]);
 
-  dontAddPrefix = true;
-  configureFlags = [ "--prefix" "$(out)" ];
+  prefixKey = "--prefix ";
 
   meta = with lib; {
     description = "A program for proof-tree visualization";