One of the most expected features is the Just in Time Compiler. Compiler promises significant performance improvements, albeit not always within the context of web requests.
PHP 8.0 comes with support for Union Types. In the versions so far, you could only declare a single type for properties, parameters, and return types. From version 8.0, you can declare more than one type for arguments, return types, and class properties.
As of PHP 8, we’ll be able to use attributes. The goal of these attributes, also known as annotations in many other languages, is to add meta data to classes, methods, variables and what not in a structured way.
As PHP 8 is still under development, we could see several changes before the final release. By the moment the Feature Freeze comes (end of July 2020) no further language features can target 8.0 anymore.
We’ll keep track of these changes.