This is a good idea for production, but not a good idea when at the “learn from a book” stage. You always should use the exact versions specified in the book unless you are sufficiently familiar with the subject matter to make the necessary changes.
In this specific case, the change is extremely minor, so it’s up to you. If you want to use latest you can, but you’ll want to do json_response(response, 200) instead of json_response(response, 400). My recommendation is to stick to the book versions while learning from the book. There are very few things different between the book version and the latest Absinthe version, but there are enough that it can confuse beginners. Go through the book till you have some comfort with it, then do your new project on the latest version.


















