Sure, but why implement a novel language with said feature if your concern is a harness ... not on implementing a brand new language with this feature?

Rust can't even dynamically link!

I'm super on board the rust train right now & super loving it. But no, code hot loading is not common.

Most code in the world is dead code. Most languages are for dead code. It's sad. Stop writing dead code (2022) was no where near the first, is decades and decades late in calling this out, but still a good one. https://jackrusher.com/strange-loop-2022/