you didn't mention one technique that is possible: Partial Application.

I have written several article showing how e can us that to create modular code

* https://blog.devgenius.io/khipu-rapid-and-sustainable-software-creation-in-swift-using-engineering-and-science-principles-312a933cce57?sk=8359f48cc06571e53de156db8cbc005c

* https://decodemeester.medium.com/fully-declarative-swift-for-real-world-projects-9b6ee9403f4c?source=friends_link&sk=fb421abb99432831b6ecb8ac8d57ebf8

* https://decodemeester.medium.com