mr_noodle, firstly thanks for answering.

1. You'll noticed that I haven't mentioned type safety as the main enabler of shipping faster, but rather better tooling and less/more explicit errors which are deriving from it.

One can code with TextEdit, or Vim, or Emacs, or Xcode or Visual Studio or IntelliJ IDEA. And I assume you know what I'll say next (I don't want to shift the conversation in that direction though).

2. Truth being told, type information always exists. It's either explicit and available to the tools you are using and also right in front of your eyes, or it can all exist in your head. My argument is that the latter is less optimal for larger projects or larger teams or libraries that are meant for others to use.

3. The above is also the reason I tried to better understand your perspective here by framing it to your experience, development process (I confess that I have no idea if you are working with a team or alone), and your application (once again I have no idea if you are working on a single code base, Hazel, or you have to maintain multiple products or change gears ever).

I did read most of the posts on this topic and, as far as I can tell, the feedback expressed in these posts is from the point of view of "if I'd be to rewrite my existing iOS or Mac app in Swift, what would I win?". Please don't get me wrong, I do believe it's a very valid perspective. But I also hope we can agree that it's just one side of the coin when looking at a new programming language (and a coin only has two sides while there are many more in this case :-).