SSL connect error

warning: spurious network error (3 tries remaining): [35] SSL connect error (Recv failure: Connection reset by peer)

ref: https://stackoverflow.com/questions/41937618/cargo-is-unable-to-download-a-file-due-to-a-ssl-connect-error

Try something like:

CARGO_HTTP_CHECK_REVOKE=false cargo add xxx

Or

Create ~/.cargo/config.toml and add

[http]
check-revoke = false