Update: The Core Spring 5 Certification in Detail book has been moved to Kobo.
I am happy to announce that my book Core Spring 5 Certification in Detail is now completed! Thanks to all readers for the patience. Thanks for the kind words left here in the comments and on Leanpub. I also want to extend a special thanks to all those who have paid for the book, regardless of the amount – your contributions have really encouraged me.
Happy programming and, for all those who aim to become certified: Best of luck with the exam!