This Ruby typechecker is a similar approach to Facebook's "Hack" language, incrementally upgrading their legacy (PHP) codebase to a new statically-typed languag

This Ruby typechecker is a similar approach to Facebook's "Hack" language, incrementally upgrading their legacy (PHP) codebase to a new statically-typed language instead of rewriting everything in a new language. https://code.facebook.com/posts/264544830379293/hack-a-new-programming-language-for-hhvm/ https://code.facebook.com/posts/264544830379293/hack-a-new-p...