It started out as compiling VBScript but from my understanding it became its own beast, with all kinds of bells and whistles. Yes, definitely there can be vali

It started out as compiling VBScript but from my understanding it became its own beast, with all kinds of bells and whistles. Yes, definitely there can be valid reasons to write your own language/compiler etc. Of course, the size of the Facebook code base, not to mention engineering team, put it in a clear class of its own. And the Hack project was run by people with extensive experience in compilers and type systems, not a summer intern... hah. But yeah, it’s not a bad idea in all cases. Facebook, google, Microsoft and many others have invented new languages and/or written compilers. And I’m sure there are valid reasons for a small organization to do it as well — but I fail to see what made it justified in this case. Then again the product didn’t go belly-up, so there’s that.