The swift scalability problems start coming up around 70k lines of code, so for the typical case of 1 or 2 developers it doesn't come up. But if you start gett

The swift scalability problems start coming up around 70k lines of code, so for the typical case of 1 or 2 developers it doesn't come up. But if you start getting a large codebase: * indexing will take forever * xcode will beachball continuously * the debugger will crash because the codebase is too much to handle * build times will be 4-5x more than the equivalent obj-c codebase * startup times will balloon significantly if you have many separate libraries, since using swift forces you to use dylibs. 60-100 libraries will mean 3-5 seconds being added to your app startup time They are all solvable problems, but it will take several years before they are fixed. But I don't think swift will be better than C++ development, since they are both similar languages as far as compiler tradeoffs go. I notice some lag even in small swift projects compared to objective-c, but it isn't major enough to worry about.