epr VS himalaya

However, if you don't need all the bells and whistles of Foliate and Koreader, and you are willing to carry out some trials and errors, consider exploring other simpler options like epr/epy, in Linux you can use any terminal of your choice, whereas in Android probably you'll be better off using Termux (a simple pip install epr-reader should do).

I occasionally use epr to read epubs in a terminal. Works pretty well.

https://github.com/wustho/epr

Before you going deeper, take a look at himalaya if it fit to your needs.

https://github.com/soywod/himalaya this one also is a thing, has a vim plugin too

Take a look at Himalaya: https://github.com/soywod/himalaya

You can use himalaya for that

We live in a time of a Renaissance of terminal tools. I recently discovered Himalaya[1], a command line tool for email, and I really like it. I'm also interested in exploring a new tool for calendar called qcal[2]. I'm kicking around writing a chat client for GroupMe for the terminal right now. That way I could finally ditch pidgin.

Like the OP, I spend all day in tmux these days, which is in many ways the most superior UI[3]. As a bonus, CLI tools are often cross-platform and very easy to write.

1: https://github.com/soywod/himalaya