Like...everything?

Create a service that starts on boot:

    cat > /etc/systemd/example.service << EOF
    [Unit]
    After=network.target

    [Service]
    User=example
    ExecStart=/usr/local/bin/example

    [Install]
    WantedBy=multi-user.target
    EOF

    systemctl enable --now example

And the harder things get, the bigger the advantage. Like if you want to mount a disk, create a socket, and then afterward start unprivileged service...all very simple.