local.conf

<?xml version='1.0'?>
<!DOCTYPE fontconfig SYSTEM 'fonts.dtd'>
<fontconfig>
  <match target="font" >
    <edit mode="assign" name="autohint">  <bool>true</bool></edit>
    <edit mode="assign" name="hinting">   <bool>false</bool></edit>
    <edit mode="assign" name="lcdfilter"> <const>lcddefault</const></edit>
    <edit mode="assign" name="hintstyle"> <const>hintslight</const></edit>
    <edit mode="assign" name="antialias"> <bool>true</bool></edit>
    <edit mode="assign" name="rgba">      <const>rgb</const></edit>
  </match>

  <match target="font">
    <test name="pixelsize" qual="any" compare="more"><double>15</double></test>
    <edit mode="assign" name="lcdfilter"><const>lcdlight</const></edit>
    <edit mode="assign" name="hintstyle"><const>hintnone</const></edit>
  </match>

  <match target="font">
    <test name="weight" compare="more"><const>medium</const></test>
    <edit mode="assign" name="hintstyle"><const>hintnone</const></edit>
    <edit mode="assign" name="lcdfilter"><const>lcdlight</const></edit>
  </match>

  <match target="font">
    <test name="slant"  compare="not_eq"><double>0</double></test>
    <edit mode="assign" name="hintstyle"><const>hintnone</const></edit>
    <edit mode="assign" name="lcdfilter"><const>lcdlight</const></edit>
  </match>

</fontconfig>