Found in 3 comments on Hacker News
runevault · 2017-04-12 · Original thread
There's actually a book on this topic from the guy who did Dothraki for the GoT show. Haven't read it yet though I did buy it at some point. (no affiliate link)

gliese1337 · 2016-02-26 · Original thread
FontForge has a tutorial: There's also a basic introduction to font design in David Peterson's book:

I've been meaning to learn how to create fonts for my own conlanging purposes for a few months now, but haven't quite gotten around to it yet.

chc2149 · 2015-05-06 · Original thread
Here it is for pre-order!

He told me it covered the essentials of language construction as far as his methodology goes, but I think it offers some insight into the development of other major and not-so-well-known conlangs as well.

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