Writing the uniqueness validations yourself is easy so I felt it was better to leave this up to the developer

But it sounds like the library could use some way to setTouched()

Wondering how to get field state from multiple fields at once? People coming from Redux-Form might be wondering where the equivalent of Redux Form's Fields component is, as a way to get state from several fields at once. The answer is that it's not included in the library because it's so easy to write one recursively composing Field components together.