My preferred juliamono font features

80-juliamono-fontfeatures.conf

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE fontconfig SYSTEM "fonts.dtd">
<fontconfig>
  <description>Enable select opentype features for JuliaMono.</description>

  <!--
	  Typographic features are provided on a per-typeface basis.
	  Tables with all available features are available here:
	  https://en.wikipedia.org/wiki/OpenType_feature_tag_list 

      Also read the fontconfig user spec:
      https://www.freedesktop.org/software/fontconfig/fontconfig-user.html
  -->

  <match target="font">
    <test name="family" compare="eq" ignore-blanks="true">
      <string>JuliaMono</string>
    </test>
    <edit name="fontfeatures" mode="append">
      <string>ss01 on</string>
      <string>ss02 off</string>
      <string>ss03 on</string>
      <string>ss05 on</string>
      <string>ss06 on</string>
      <string>ss07 on</string>
      <string>ss08 on</string>
      <string>ss10 on</string>
      <string>ss11 on</string>
      <string>ss12 on</string>
      <string>ss13 on</string>
      <string>ss14 on</string>
      <string>ss15 on</string>
      <string>ss20 on</string>
      <string>zero on</string>
      <string>cv01 on</string>
      <string>cv02 on</string>
      <string>cv03 on</string>
    </edit>
  </match>
</fontconfig>