[swift-evolution] A case for postponing ABI stability

[David Hart]

Hello swift-evolution,

ABI stability is an important feature which many Swift users are looking forward to. If I understand it correctly, once it’s here, the Standard Library becomes part of that ABI and only additive and backwards-compatible changes can be done. Seeing how we are still heavily modifying the Standard Library this year (Strings), wouldn’t it be wiser to let those changes simmer under the scrutiny of the broader community of Swift users for a year before we make it into the ABI?

ABI compatibility is important. Some projects need it, but I think that most projects (most Apple platform third-party applications) would only mildly benefit from it. But I want to make sure the Standard Library has had enough time to mature before we set it in stone.

Regards,
David.