diff --git a/pkgs/development/libraries/haskell/ghc-heap-view/default.nix b/pkgs/development/libraries/haskell/ghc-heap-view/default.nix
index 24520869551..679ced622d9 100644
--- a/pkgs/development/libraries/haskell/ghc-heap-view/default.nix
+++ b/pkgs/development/libraries/haskell/ghc-heap-view/default.nix
@@ -6,9 +6,9 @@ cabal.mkDerivation (self: {
   sha256 = "1qi7f3phj2j63x1wd2cvk36945cxd84s12zs03hlrn49wzx2pf1n";
   buildDepends = [ binary transformers ];
   postInstall = ''
-      ensureDir "$out/share/ghci"
-      ln -s "$out/share/$pname-$version/ghci" "$out/share/ghci/$pname"
-    '';
+    ensureDir "$out/share/ghci"
+    ln -s "$out/share/$pname-$version/ghci" "$out/share/ghci/$pname"
+  '';
   meta = {
     description = "Extract the heap representation of Haskell values and thunks";
     license = self.stdenv.lib.licenses.bsd3;