Well, OO libraries for lua were not popular nor
standardized until not long ago, so, the default suggestion for it was actually to create your own OO lib, which many projectes ended up doing (mostly in the same way), which led to some trouble.
For replacing nginx with lua, that is curious. Openresty is not being used? No web framework? (lot of lua dead web frameworks in the road, by the way)
Also, "creating your own reality" is usually a bad thing in any language. That usually happens when you're developing something alone, for long and didn't give maintenance to other peoples code much in the past.
In another related point: lua is NOT supposed to be used as glue/extension code. It was designed so that it would be easy to do so. It is that "you can" more than "you should".
Lua doesn't come with batteries included, by design and doesn't have a plethora of libraries available or (coff coff) easy to pick from, but, they do exist and they do solve most problems. Nonethless, truth be told, most of the good api for Lua one sees nowadays, was not available 1 or 2 years ago or not mature enough.
To conclude, lack of type hinting in Lua or optional static typing can create problems for bigger problems if good design, testing and documentation is not enforced from day 1. Most scripting languages suffer from this. You guys could try "ravi" to get this (almost) for free.
