If you're looking for static typing a dynamic language is going to be a poor fit. I find a place for both. I love Rust, but trying to write a tool that consumed a GraphQL API with was a brutal exercise in frustation. I'd say that goes for typing of JSON or YAML or whatever structured format in general. It's refreshing being able to just work with data in the form I already know it's in. Ruby can be an incredibly productive language to work with.

If you're looking for static analysis in general, please note that there are mature tools available. Rubocop¹ is probably the most popular and allows for linting and code formatting. Brakeman² is a vulnerability scanner for Rails. Sorbet³ is a static type checker.

The tooling is there if you want to try things out. But, if you want a statically typed language then that's a debate that's been going since the dawn of programming language design. I doubt it's going to get resolved in this thread.

¹ - https://github.com/rubocop/rubocop

² - https://brakemanscanner.org/

³ - https://sorbet.org/

I want to use Lua for more tasks

I’ve used rubocop and sorbet. But now that I’ve used TypeScript it’s clear there’s no comparison. TS will even analyze your regex patterns. Every update gets better. I’m eagerly waiting for the day they add analysis for array length and ranged numbers.