Have you tried Odin? Its a great language thats also a “better C” but takes more Go inspiration than Zig.
Odin doesn't (and won't ever according to its creator) implement specific concurrency strategies. No async, coroutines, channels, fibers, etc... The creator sees concurrency strategy (as well as memory management) as something that's higher level than what he wants the language to be.
Which is fine by me, but I know lots of people are looking for "killer" features.
Wonderful language!
https://www.youtube.com/watch?v=xt1KNDmOYqA is worth a watch.