As long as there is any structure or internal logic to what the program does, it can be reflected in its types. For your example of a server, look at the Serva

As long as there is any structure or internal logic to what the program does, it can be reflected in its types. For your example of a server, look at the Servant library in haskell. It allows you to define type safe routes and links, ensuring that your program exactly matches the API, and that no links are ever broken. https://haskell-servant.github.io/ https://haskell-servant.github.io/