Dependencies should be upgraded for rAPIREG project:
cargo build
$ cargo build Updating crates.io index error: failed to select a version for the requirement `ring = "^0.11.0"` candidate versions found which didn't match: 0.16.20, 0.16.19, 0.16.18, ... location searched: crates.io index required by package `cookie v0.9.1` ... which satisfies dependency `cookie = "^0.9.1"` of package `rocket v0.3.16` ... which satisfies dependency `rocket = "^0.3.16"` of package `docker-registry-api v0.1.0 (/usr/home/dereckson/dev/nasqueron/api/docker-registry-api)`
Could be as simple as upgrade Rocket version?