I came across a couple of very interesting PHP libraries today.
The first one is thecodingmachine/safe. This library wraps all PHP functions that return false on failure into another function that throws the exception instead. Think of all those file_get_contents() and json_decode() situations you had to code around. Not anymore. You can easily have them throw exceptions now. Read this blog post for more details.
The second one is rectorphp/rector. It is in fact mentioned in the documentation for the above library. Rector is a refactoring (reconstruction and upgrade) tool that can easily change large chunks of your code. Think of function renaming, parameter changes, and such. Read these blog posts for more details: part 1, part 2, and part 3.