It is interesting through ;-)

Personally, I will probably introduce some of it to a project I'm working on. Here's why:

* It's relatively conservative - almost of all its work is done in compile time. Once you have a binary and it went through testing then Manifold is irrelevant.

* It's open source - I know it's not the same as "support" but the project has been around for a while and the author is active.

* Worst case scenario I can remove it - it would suck since I will need to rewrite code. But the compiler will point me at the exact lines of code I need to fix.

A team I was on decided against Manifold precisely because we wanted to keep up with Java's twice-yearly version updates, and we didn't want a bespoke compiler plugin to lock us to an older version.

I think Manifold is extremely cool, and it does look like they're keeping up with the latest -- but the deep compiler magic it relies on really makes me nervous.