One **huge** thing in #rustlang ist that a single #![no_std] annotation in your code base can make you a much better programmer...
(tells the compiler: no OS assumed and no heap implementation available by default)
It had become my primary workflow:
- no_std, no_alloc lib.rs for business logic
- evtl std main.rs but maybe decide later to port to a microcontroller or run it as wasm in the browser