My impression is that It's a mix of C and PHP... I literally learned it in a few days (I'm sure some nuisances escaped me though).
What zephir is missing are variable references and anonymous functions, which makes porting PHP code to zephir hard, because you'll have to refactor it a bit
Thank you all. I think Zephir is the really good idea. So... I'll learn Zephir and recode my REST API. And thanks a lot to the Phalcon Team for having created this language !