TL;DR: it was very much worth it. Performance improvements have been significant. It was not easy to do the migration, and it took us about a year to make our full code base HipHop compliant. We had to make many changes on our side so about a million of lines of code would be compiled on HipHop but that wasn’t it- we also needed to make several changes to HipHop itself...but back to our epic tale!

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