diff --git a/pkgs/by-name/ne/netgen/package.nix b/pkgs/by-name/ne/netgen/package.nix
index 46086c442524..d034a54c7fdb 100644
--- a/pkgs/by-name/ne/netgen/package.nix
+++ b/pkgs/by-name/ne/netgen/package.nix
@@ -78,6 +78,9 @@ stdenv.mkDerivation (finalAttrs: {
     substituteInPlace python/CMakeLists.txt \
       --replace-fail ''\'''${CMAKE_INSTALL_PREFIX}/''${NG_INSTALL_DIR_PYTHON}' \
                      ''\'''${CMAKE_INSTALL_PREFIX}/''${NG_INSTALL_DIR_PYTHON}:$ENV{PYTHONPATH}'
+
+    substituteInPlace ng/ng.tcl ng/onetcl.cpp \
+      --replace-fail "libnggui" "$out/lib/libnggui"
   '';
 
   nativeBuildInputs = [
@@ -121,11 +124,6 @@ stdenv.mkDerivation (finalAttrs: {
     (lib.cmakeBool "ENABLE_UNIT_TESTS" finalAttrs.finalPackage.doInstallCheck)
   ];
 
-  # Tcl script used by netgen need to be aware of environment NETGENDIR
-  postInstall = ''
-    wrapProgram "$out/bin/netgen" --set NETGENDIR "$out/bin"
-  '';
-
   # mesh generation differs on x86_64 and aarch64 platform
   # tests will fail on aarch64 platform
   doInstallCheck = stdenv.hostPlatform.isx86_64;
diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index d07af8fb5894..3da85187ea93 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -9399,7 +9399,7 @@ self: super: with self; {
 
   netdisco = callPackage ../development/python-modules/netdisco { };
 
-  netgen = toPythonModule (pkgs.netgen.override { python3Packages = self; });
+  netgen-mesher = toPythonModule (pkgs.netgen.override { python3Packages = self; });
 
   nethsm = callPackage ../development/python-modules/nethsm { };