[seandougall]

> I keep hearing the language is going to be stable "soon"

I think you may be referring to the promises of ABI stability? They kept promising that "soon" starting around Swift 3 (IIRC) and kicking the can down the road for a while there, but it is stable now on Apple's OSes. But I don't recall seeing promises of source stability back then; they were pretty open about the fact that the language was still evolving.