[asterite]

That's about speed (though I think Truffle/Graal make an app consume more memory). Crystal is type-safe, and no optimizing VM can do that for Ruby.

Not that type-safety is a killer feature, but that's just one difference.

[benbristow]

https://medium.com/byteconf/stripe-is-building-a-ruby-typech...

Stripe are trying to solve that issue.

[AsyncAwait]

That's still not the same as a compile time type-checker, it still relies on the interpreter.