Writing pure functions really helps with maintainability: https://en.wikipedia.org/wiki/Pure_function https://en.wikipedia.org/wiki/Pure_function You will alwa

Writing pure functions really helps with maintainability: https://en.wikipedia.org/wiki/Pure_function https://en.wikipedia.org/wiki/Pure_function You will always have side effects but you can try to isolate the bits that are impure and write the rest of your software in a purely functional manner.