https://os.phil-opp.com
https://github.com/helena-project/tock
https://www.redox-os.org
https://github.com/redox-os/tfs
https://github.com/intermezzOS/kernel
The biggest application example:
https://github.com/servo/servo
And some self promotion:
https://github.com/bluejekyll/trust-dns
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I encourage all programmers to check it out. You may discover like me, that Rust is a compiler and language which guards against all the hard learned lessons I've had over my career. It's an amazing language to program in.
