Does it make sense to completely avoid using the keywords "public" and "open" in the main target program?

We have a large iOS 150K + app of code, a quarter of its code is Swift.

I am currently writing a separate module: iOS dynamic infrastructure, where I carefully use the public

, internal

, fileprivate

, private

. This work made me think about the main goal of our application as a large Swift module that could use all its classes at the most internal

level , and the reason for this is that these classes are not accessible from outside our application, but only from the inside.

I don't have time to dive into the internals of Swift and do an experiment to measure performance differences, so I ask if anyone has any insight if:

• this usage practice public
  
  or open
  
  for application classes makes sense
• if it makes a performance difference like incremental compile time.

Of course, code that connects with Objective-C is outside the scope of this question.

Background: In Objective-C, C, and C ++, putting as much as possible in files .cpp

and forwarding everything in files .h

makes a big difference in terms of incremental compile times, so I'm wondering, practice should be considered for Swift applications.