[ltratt]

PHP is an... interesting... language to implement. The de facto standard PHP interpreters have become very fast over time. It's been a long time since I measured HHVM, but it always used to have very good warm-up time. I always felt it was a bit of a pity that no-one took on HippyVM (PHP in RPython https://github.com/hippyvm/hippyvm): it implemented a very large chunk of the language, had decent performance, but still some low-hanging fruit to improve (I had some fun making fairly substantial performance improvements to some aspects of it). It would be interesting to compare HippyVM and Graalphp once they implement equivalent chunks of the language, especially if someone takes on maintainership of HippyVM!