Fonts on Linux, Chapter Three: About Freetype2, Fontconfig and Infinality (RIP)

Let's agree on a few things:

• the original infinality patched freetype packages are outdated and cannot ne used anymore
• at least 50% of what infinality did to improve the looks is about sane defaults, a careful configuration and installing the right fonts
• according to this one will need at least freetype 2.7.1 to get better looks; don't ask me to explain better, just read the whole article.
• there is some other stuff that infinality was capable of via environment variables; this can not be achieved even with newer fontconfig versions, but i daresay that most people moaning about how infinality was so much better, didn't even tweak these features.
• there's some effort to apply the infinality patches to current freetype versions. people who really want infinality should watch out for these patches, not the old freetype2-infinality packages. one place to find them is here (note, only freetype2 is up-to-date, fontconfig has to be done manually
• one might further benefit from re-compiling freetype2 with MS's ClearType
• one might benefit even further from installing actual Microsoft fonts (they don't spy on you!), and setting fontconfig up accordingly

I strongly recommend to read these resources:

• https://gist.github.com/cryzed/e002e7057435f02cc7894b9e748c5671
• https://www.freedesktop.org/software/fontconfig/fontconfig-user.html
• https://wiki.archlinux.org/index.php/font_configuration
• https://www.reddit.com/r/archlinux/comments/5n8b05/guide_perfect_fonts_without_the_outdated/

i apologize that most of these instructions are for archlinux; but i guess debianites will have to do some manual compiling anyhow, where an AUR PKGBUILD can be quite useful.
stretch's freetype2 is at 2.6.something, so not enough according to this! and i could not find a backported larger version.

Source