I've been lightly following this for a while now (and it looks really good) but sadly so far I see hardly any benefit in using Lua without openresty for web development (I have two fun projects using Lapis and some more boring stuff in production in pure openresty+Lua, without any external libs). Why openresty? Simply for performance reasons - when using Python the ecosystem is just exponentially bigger than Lua's and for the stuff I need Flask usually is the right answer and gives quick results and stable(!) libraries for everything are at hand.