Eloquent Ruby is one of my favorite books, too. That book really motivated me to learn how programming languages work. Here are a few other books I found to be enjoyable and well-written: Programming Erlang by Joe Armstrong Programming Elixir by Dave Thomas Seven (more) Languages In Seven Weeks by Bruce Tate Think Bayes, Think OS, How To Think Like A Functional Programmer (Think OCaml) and The Little Book of Semaphores by Allen B. Downey
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