anchor.diff:    buildInputs = [
       zlib expat openssl
       libjpeg libpng libtiff freetype fontconfig libpaper jbig2dec
  -    libiconv ijs lcms2 bash
  +    libiconv ijs lcms2 bash openjpeg
     ]
     ++ lib.optional x11Support xlibsWrapper
     ++ lib.optional cupsSupport cups
  
positive.code:     export CCAUX=$CC_FOR_BUILD
      ${lib.optionalString cupsSupport ''export CUPSCONFIG="${cups.dev}/bin/cups-config"''}
  
      # requires in-tree (heavily patched) openjpeg
      rm -rf jpeg libpng zlib jasper expat tiff lcms2mt jbig2dec freetype cups/libs ijs
  
      sed "s@if ( test -f \$(INCLUDE)[^ ]* )@if ( true )@; s@INCLUDE=/usr/include@INCLUDE=/no-such-path@" -i base/unix-aux.mak
      sed "s@^ZLIBDIR=.*@ZLIBDIR=${zlib.dev}/include@" -i configure.ac
  
negative.code: { config, stdenv, lib, fetchurl, pkg-config, zlib, expat, openssl, autoconf
  , libjpeg, libpng, libtiff, freetype, fontconfig, libpaper, jbig2dec
  , libiconv, ijs, lcms2, fetchpatch, callPackage, bash, buildPackages, openjpeg
  , cupsSupport ? config.ghostscript.cups or (!stdenv.isDarwin), cups
  , x11Support ? cupsSupport, xlibsWrapper # with CUPS, X11 only adds very little
  }:
  