letmein-systemd has no features set by default.
[dependencies] letmein-systemd = { version = "7.2.0", features = ["tcp", "unix"] }
Affects letmein-systemd::tcp_from_systemd…
letmein-systemd::tcp_from_systemd
Affects letmein-systemd::unix_from_systemd…
letmein-systemd::unix_from_systemd