Good work. I'm happy to see this for Redox. There are numerous implementations of capabilities now, and they confirm that the concept really does simplify access control and sandboxing.

Could I get some examples? I'm interested in learning more.

Implementations include seL4, Barrelfish, Google Fuchsia OS, Capsicum, and a slew of research systems too long to list. It's also worth checking out tangential things like the E programming language and Google's old Caja project.

there's also capsudo by kaniini

https://github.com/kaniini/capsudo