After almost 20 years of building software, I mostly read books.

Not any books; Programming books put me to sleep on about 5 pages.

I prefer books where programming languages are just for writing examples rather than the center of attention.

I prefer books where I can read about experiences and software development fundamentals; those will retain their value as they age.

I prefer books about best practices, optimizations, and study cases.

System design books are also good, helping you to tease your mind to think out of the box.

The Pragmatic Programmer by Dave Thomas and Andy Hunt.

It is one of these books. I come back to read this one from time to time.

Do you have any books at hand?