Introducing PHPSandbox Play | implenton
I have been using CodePen, CodeSandbox, and similar services to try out things or throw together a prototype. While these are great for JS, CSS, and HTML, they can't run PHP.
3v4l is excellent for teeny code snippets, but it's not really for prototyping; its selling point is that it can run more than 250 PHP versions.
The good news is... PHPSandbox just launched Play that
is a playground to try Composer packages. With it, you can try 350k+ packages using a standard PHP v8.1 environment.