To disable font hinting in Arch linux create following file
# vim ~/.config/fontconfig/conf.d/10-hinting-slight.conf
<?xml version="1.0"?>
<!DOCTYPE fontconfig SYSTEM "fonts.dtd">
<fontconfig>
<match target="pattern">
<edit name="hintstyle" mode="assign"><bool>false</bool></edit>
</match>
</fontconfig>
That's it! Restart Chromium or Atom and you will see changes.
UPDATE 12.09.2016. Today freetype2 (2.6.5-2 -> 2.7-2) updated and font is ugly again. There is remark in pacman.log
The Arch-specific FT2_SUBPIXEL_HINTING has been removed. Subpixel hinting is now configured in /etc/profile.d/freetype2.sh.
So we should change something in /etc/profile.d/freetype2.sh
# sudo vim /etc/profile.d/freetype2.sh export FREETYPE_PROPERTIES="truetype:interpreter-version=35"
But still fonts in Chromium and Atom are ugly, so I decided downgrade freetype2 (2.7-2 -> 2.6.5-2).
cd ~/temp wget https://archive.archlinux.org/packages/f/freetype2/freetype2-2.6.5-2-x86_64.pkg.tar.xz sudo pacman -U freetype2-2.6.5-2-x86_64.pkg.tar.xz # add freetype2 to IgnorePkg in pacman.conf # sudo vim /etc/pacman.conf IgnorePkg = freetype2