After reading An Apple Library Primer and watching Meet mergeable libraries (both really good resources) I'm sold on mergeable libraries. In my company we're working with static libraries as much as possible (both for precompiled dependencies and for our own Xcode projects). I can see that switching to mergeable libraries would (at least) improve iteration time because mergeable libraries would only be merged in release configs by default. You made it sound like it's "the holy grail of libraries". However, before starting the migration process I'd like to know: Is there any drawback to (merged) mergeable libraries when compared to using static libraries? I got the idea that mergeable libraries behave "almost" like static libraries after being linked "statically" with the app. What differences can I expect? Is there any situation where it's better to use static libraries instead of mergeable libraries? Thank you!