anchor.diff:    '' + optionalString enableSpelling ''
       sed -i -e 's|=.*find_lib.*|= "${gtkspell}/lib/libgtkspell.so"|'   \
         src/gtkspell.py
  -  '' + optionalString enableLaTeX ''
  -    sed -i -e "s|try_run(.'dvipng'|try_run(['${texLive}/bin/dvipng'|" \
  -           -e "s|try_run(.'latex'|try_run(['${texLive}/bin/latex'|"   \
  -           -e 's/tmpfd.close()/os.close(tmpfd)/'                      \
  -           src/common/latex.py
     '';
   
     buildInputs = [
  
positive.code: , enableRST ? true
  , enableSpelling ? true, gtkspell ? null
  , enableNotifications ? false
  , enableLaTeX ? false, texLive ? null
  }:
  
  assert enableJingle -> farstream != null && gst_plugins_bad != null
  
negative.code:   ] ++ optionals enableJingle [ farstream gst_plugins_bad libnice ]
      ++ optional enableE2E pythonPackages.pycrypto
      ++ optional enableRST pythonPackages.docutils
      ++ optional enableNotifications pythonPackages.notify;
  
    postInstall = ''
      install -m 644 -t "$out/share/gajim/icons/hicolor" \
  