[zomgbbq]

I'm going to answer but I should preface by saying I'm not going to try to proselytize you to Swift. If it doesn't work for you and you're happy with Objective-C, then by all means do what makes you happy and keeps you productive. I have a couple of apps that have about 50k lines of Swift, one also with 60k lines of Objective-C and another with 40k lines of Objective-C. We use MVVM as well as a fairly involved mechanism of VM abstraction with intercommunication using RAC. Common code is in a cocoapod as well as other third-party dependencies otherwise the other target is the iOS app itself. I think LOC is a poor metric to measure complexity, but it does have a relevance to compile time. Others have also said that Swift and Xcode are not perfect, but as an engineer programming in Swift makes me quite happy.

[mahyarm]

Aha! You haven't hit the LOC barrier that starts to make swift & xcode/source kit act like bsaul described. At around 100kloc you will start to get that experience with swift. While an equivalent 100-200kloc line app written in objective c will work quite fine with xcode. You'll start noticing some degradation as you get to 60-70kloc. You also have a simple module structure, which makes things better.

You can see it happen pretty plainly with a simple codegen script creating a bunch of dummy code up to X lines of code.

[G4BB3R]

Then, it's not Swift that is not production ready, but XCode that is crap :)

[mahyarm]

Most of this crap comes from the compiler / sourcekit itself, which is a major part of the language. It has scalability problems.