https://pawelurbanek.com/rails-dynamic-config

Config variables should never be embedded directly in the codebase. It is a common practice to extract them into a separate configuration layer. A standard approach for Ruby on Rails apps is to use static ENV variables that can only be changed via a release process. In this blog post, I’ll describe the use cases for using dynamic config variables that can be modified on the fly. I’ll also share a simple way to start using them in your app without including additional gem dependencies.