When I write Rust code most of my errors typically get caught by my language server. Unfortunately, this doesn't help much with making builds faster, though it may reduce the number I may have to do.
Useless for graphics and GUI programming.
For GUI programming, you can use a toolkit that have a preview extension that updates in real time as you type. For example, Slint does that.
It doesn't do that for Rust code being called from UI.