[pornel]

Carbon devs explicitly say use Rust if you can.

Non-trivial C++ programs depend on OOP design patterns, webs of shared-mutable objects, and other features which Rust doesn't want to support (Rust's safety also comes from not having certain features that defeat static analysis).

Rust really needs things written the Rust way. It's usually easier with C, because it won't have clever templates and deep inheritance hierarchies.

Even if your goal is to move to Rust, it may make sense to start with Carbon or Circle to refactor the code first to have more immutability and tree-like data flow.