> Porting TypeScript to Go in 7.0 doesn’t seem like bad engineering.

They needed 10x speedup and it was not possible with the current language. And they chose Go, because they could retain 1:1 architecture in most cases. So whether or not it was well engineered, is not so clear. They did not choose Rust because they would have needed to redesign the whole architecture.

In the case of Bun, it smells more like bad engineering, so I am not sure if these are comparable.