The problem with configuration is that it’s only marginally useful to statically enforce that “this should be an IP address” or “this should be a port” People

The problem with configuration is that it’s only marginally useful to statically enforce that “this should be an IP address” or “this should be a port” People rarely waste time because they put a number where they should have put an IP address. People waste a lot of time because they don’t know what IP address to put in there. Look at any real life production nginx or kubernetes config and ask yourself an honest question — how much would a static type system actually help me in writing this config? We understand what types the configuration fields want — that’s trivial. We spend all of our time finding the correct values for those types.