Here are some books that I highly recommend.

For C++, there is the curated list on StackOverflow: The Definitive C++ Book Guide and List. Nothing I could add to that list, or take away.

For JavaScript (ES6), I've been out of the loop too long. I suspect books like Eloquent JavaScript and JavaScript: The Good Parts are out of date, but I found them to be a great help back in the day.

For F#, I've read about a dozen books on the topic. Only one book have I found to be useful so far:

• The Book of F#, by Dave Fancher, a fantastically fabulous book
• disclaimer: I haven't read "Expert F# 4.0" yet, which I hope and expect will be good, even if the reviews call it "preachy"

For agile, I've really enjoyed these books:

• The Scrum Guide, by Schwaber and Sutherland, is nice, very short, definitive, and free (PDF)
• Succeeding With Agile, by Mike Cohn, is a "must have" book for agile
• How To Implement Scrum in 10 Easy Steps, by Kelly Waters, is an online article, but I'd be remiss if I didn't call it out here. Scrum really is that simple... in theory.

For general development, I have these heavily dog-eared books on my top shelf:

• Writing Solid Code, by Steve Maguire
• Code Complete, by Steve McConnell
• Clean Code, by Robert C. Martin
• Design Patterns, by Gamma, Helm, Johnson, and Vlissides
• AntiPatterns, by Brown, Malveau, McCormick, and Mowbray

On my short queue of books to read that have been highly recommended to me:

• Refactoring, by Martin Fowler, et al
• The Pragmatic Programmer, by Hunt and Thomas
• Growing Object-Oriented Software, Guided by Tests, by Freeman and Pryce

What are some book recommendations you would like to share?