Just a note, Kong is built on OpenResty and has a wide ecosystem of plugins already built in lua with it's own development kit to speed up development time of custom functionality.

Cannot urge how many times it's saved my ass. Not to mention it's very easy to scale!

Kong has ran well in production for us, but development can be slow due to the pure LUA scripting. I think some of the problems they have are fixed in an updated version, but there is no update path that doesn't involve re-writing every custom code we have.

We're switching to openresty + LUA proxying to a co-located elixir server that will handle the access requests.

I'd be very interested in knowing what you've written that you have to re-write _every_ release, especially since you can use the OpenResty API. You'd have to do it for every OpenResty release as well. Doesn't sound right to me!

However, I do say, whatever is easier for you go for it, at the end of the day, it's business value that matters the most! If the refactor increases your business value, do it! If not? Then... don't touch it!