Versioning APIs is a critical part of building web applications, as it allows you to make changes that may otherwise break existing API users. Changing the contract between the API and the clients that depend on it is dangerous, and versioning endpoints adds flexibility and safety. Versioning is implemented in many ways - You can version with subdomains, query parameters, URL schemas, headers, and more!

When building web applications in PHP, there may be times when you want to add metadata to annotate your code that can be read by other parts of your application. For example, if you've ever used PHPUnit to write tests for your PHP code, you'll have likely used the @test annotation to mark a method as a test in a DocBlock. Traditionally, annotations like this have been added to code using DocBlocks. However, as of PHP 8.0, you can use attributes instead to annotate your code in a more structured way.

APIs are the bread and butter of the internet. The ability to interact with our applications programmatically enables interoperability and makes our lives as developers easier. Unfortunately, web applications are vulnerable to malicious actors that seek to misuse them or degrade their performance, which is why rate limiting is an important part of any API.