Using Elixir’s metaprogramming (Code.compile_quoted) and the BEAM’s Hot Code Swapping, we can transform a configuration flag into a reactive recompilation. Instead of asking if a flag is active, the system is structurally altered to execute only the necessary code.

https://dev.to/matheuscamarques/are-feature-flags-bullsht-why-your-if-is-killing-performance-and-the-planet-26bi