diff --git a/pkgs/applications/audio/vkeybd/default.nix b/pkgs/applications/audio/vkeybd/default.nix
index 279820a723f..b7b0fba2d54 100644
--- a/pkgs/applications/audio/vkeybd/default.nix
+++ b/pkgs/applications/audio/vkeybd/default.nix
@@ -16,7 +16,7 @@ stdenv.mkDerivation  rec {
     sed -e "s@/usr/local@$out@" -i Makefile
   '';
 
-  makeFlags = [ "TKLIB=-ltk8.5" "TCLLIB=-ltcl8.5" ];
+  makeFlags = [ "TKLIB=-l${tk.libPrefix}" "TCLLIB=-l${tcl.libPrefix}" ];
 
   postInstall = ''
     wrapProgram $out/bin/vkeybd --set TK_LIBRARY "${tk}/lib/${tk.libPrefix}"
diff --git a/pkgs/applications/science/electronics/tkgate/1.x.nix b/pkgs/applications/science/electronics/tkgate/1.x.nix
index 30e882a7f38..e9849d0460c 100644
--- a/pkgs/applications/science/electronics/tkgate/1.x.nix
+++ b/pkgs/applications/science/electronics/tkgate/1.x.nix
@@ -16,7 +16,7 @@ stdenv.mkDerivation rec {
 
   patchPhase = ''
     sed -i config.h \
-      -e 's|.*#define.*TKGATE_TCLTK_VERSIONS.*|#define TKGATE_TCLTK_VERSIONS "8.5"|' \
+      -e 's|.*#define.*TKGATE_TCLTK_VERSIONS.*|#define TKGATE_TCLTK_VERSIONS "${tcl.release}"|' \
       -e 's|.*#define.*TKGATE_INCDIRS.*|#define TKGATE_INCDIRS "${tcl}/include ${tk}/include ${libiconvInc} ${libX11}/include"|' \
       -e 's|.*#define.*TKGATE_LIBDIRS.*|#define TKGATE_LIBDIRS "${tcl}/lib ${tk}/lib ${libiconvLib} ${libX11}/lib"|' \
       \
diff --git a/pkgs/development/interpreters/pypy/default.nix b/pkgs/development/interpreters/pypy/default.nix
index f67c48c62d8..10d03103b1b 100644
--- a/pkgs/development/interpreters/pypy/default.nix
+++ b/pkgs/development/interpreters/pypy/default.nix
@@ -51,7 +51,7 @@ let
       # tkinter hints
       substituteInPlace lib_pypy/_tkinter/tklib.py \
         --replace "'/usr/include/tcl'" "'${tk}/include', '${tcl}/include'" \
-        --replace "linklibs=['tcl', 'tk']" "linklibs=['tcl8.5', 'tk8.5']" \
+        --replace "linklibs=['tcl', 'tk']" "linklibs=['${tcl.libPrefix}', '${tk.libPrefix}']" \
         --replace "libdirs = []" "libdirs = ['${tk}/lib', '${tcl}/lib']"
 
       sed -i "s@libraries=\['sqlite3'\]\$@libraries=['sqlite3'], include_dirs=['${sqlite}/include'], library_dirs=['${sqlite}/lib']@" lib_pypy/_sqlite3.py