Well many OCaml libraries do abstract from Lwt/Async using Functors allowing you to choose library you want to go with. But it's still not perfect since someti

Well many OCaml libraries do abstract from Lwt/Async using Functors allowing you to choose library you want to go with. But it's still not perfect since sometimes third party libraries still need to write concrete implementation of something diving into lower level, hence breaking the abstraction. This "interface" approach wouldn't work in all cases.