[nostrademons]

My experience was Go was about 2-3x slower (development speed) than Python for prototyping. Web programming, though, which is a particular strength of Python and a particular weakness of Go. YMMV, of course.

I actually really do miss list comprehensions and properties and pervasive protocols for built-in types and really concise keyword/literal syntax. I don't miss metaclasses, and I only vaguely miss decorators. (Go has struct annotations and compiler-available-as-a-library, which in some ways are better.) Properties in particular are really useful for the evolvability of code; otherwise you have to overdesign up front to avoid a big rewrite as you switch from straight struct fields to accessors.

I'm actually leaning towards Java 8 + Jython 2.7 as I consider what language to write my startup/personal projects in. Jython 2.7 gives me basically all the language features I actually cared about in Python, and it fixes the Unicode mess that necessitated Python 3. It has no GIL and solid multithreading support. The Java layer gives you all the speed of Go and more. And the interface between them lets you seamlessly use Java within your Jython scripts, so you can easily push code down into the Java layer without having to rewrite your whole product.

[jerf]

Yes, the Go web prototyping story is a bit weak. If you want to do serious development in it I think it's pretty good, because frankly for years our web frameworks in most other languages have been unbelievably contorted around not having something like goroutines in ways that we've stopped even being able to see because they're so darned pervasive, but if you just want to slam a decent site out (and there's nothing wrong with that) there's no great story there right now.

[nswanberg]

What are you considering for a prototyping datastore? Postgres? App Engine?

[nostrademons]

For prototyping I'm actually considering keeping everything in-memory, with hashtables and such (or objects that wrap them). Before you laugh, Hacker News uses this approach and it's gotten well beyond the prototyping stage.