[stickfigure]

Go quite literally has a syntax incantation for marshaling data across threads (channels). The novelty of Go is that it's language-level as opposed to library-level. It's nice, but in practice I don't think it makes a huge amount of difference.

Java also has some basic thread synchronization primitives built into the language. It's way easier than you probably think. And it gets even more interesting with the upcoming project loom, which gives you the same programming model for lightweight and real threads.

Async programming is a pox on the industry. It's very useful in rare situations that require extremely high performance, but for general business processing, function coloring adds a ton of accidental complexity.