Experss.js Deep API Reference is a derivative work from Pro Express.js. This means that this book is a more focused and concise manual for the Express.js framework. But this book has started as Express.js Guide a few years ago.
Express.js Deep API Reference is a concise book on one particular library. Unlike Practical Node.js (Apress, 2014) which covered many libraries, Express.js Deep API Reference is focused only on the single module Express.js. Of course, in places where it’s necessary to cover other related libraries, like middleware, the book touches on those as well, but not as extensively as on the framework itself.