Is this a layer that is superimposed on PHP that falls back to the default interpreter for unimplemented features or is this a fresh implementation. I suppose my question is, how reliable is this. Are the core PHP bugs going to manifest here? If a bug gets fixed on core PHP, will hack be lagging behind?
Hack runs on the HHVM engine. HHVM is fairly stable and is used by Facebook to serve over a billion web requests per today. In the past year or so developers outside of Facebook have started using HHVM to run other PHP codebases, and at present 20 of the top PHP frameworks are able to run correctly on HHVM (hhvm.com/frameworks), with 9 of the framework's test suites fully passing.
If you encounter behavioral differences or bugs when running HHVM, you can report it at our github site (hhvm.com/repo) and we will help get it resolved.
Well where is PHP core then? to my knowledge while PHP 5 was a huge step forward, PHP core did little to fix PHP stupid design flaws,for the sake of backward compatibility.
We are in a new era, libraries are more and more decoupled,so they are easy to write or rewrite,backward compatibily shouldnt be an issue when libraries are well versioned and tested across different versions.
And Wordpress folks dont care about PHP.next.Why bother with them?
Someone has to do it, and the PHP developers have proven time and again that they aren't going to. At some point the only options are to leave PHP altogether, or make your own PHP that sucks less.