Baryon is a compact 3D engine focused on fast prototyping in code. No big dependencies, no fancy run-times, GUI editors, or other magic. It's heavily ECS-oriented, and could be used as a foundation for high-level engines.
See the slides from the Rust-GameDev talk on Feb 2022.
Dependency highlights:
For a similar but more complete experience, with bigger focus on ECS, consider Dotrix. For more features and bigger community, consider Bevy. For better performance and experimental high-tech, consider Rend3.