If you want to back an open source engine that’s already very mature and has a big community, you want Godot. It’s not written in Rust, but it supports an FFI API that allows you to write your game logic in Rust. The killer feature that sets it apart from pure-Rust engines is console support.
If you want to see a skilled team with strong leadership building on a carefully designed foundation, and you’re not afraid to wait years for the payoff, there’s Bevy, which has made a splash on HN a couple times over the past year.
If you want an engine that’s comfortably mature today, and you want it to be written in Rust for no particular reason, then RG3D is the clear winner.
If you want to see a skilled team with strong leadership building on a carefully designed foundation, and you’re not afraid to wait years for the payoff, there’s Bevy, which has made a splash on HN a couple times over the past year.
If you want an engine that’s comfortably mature today, and you want it to be written in Rust for no particular reason, then RG3D is the clear winner.