When running cargo install boringtun-cli on rustc 1.76.0 (07dca489a 2024-02-04) (Alpine Linux 1.76.0-r0), I get a warning "the following packages contain code that will be rejected by a future version of Rust: daemonize v0.4.1". This version is behind even the latest version released a year ago. When building with rustc 1.79.0-nightly (0d8b3346a 2024-04-14) x86_64-unknown-linux-gnu I'm also getting unstable feature errors. Looking at the repo, daemonize is strange because its Issues tab is disabled and there are PRs trying to fix things like UB, and you may want an alternative or a fork of it.