Caddy Server: Auto-HTTPS Web Server

Install Caddy

sudo apt install -y debian-keyring debian-archive-keyring apt-transport-https
curl -1sLf 'https://dl.cloudsmith.io/public/caddy/stable/gpg.key' | sudo gpg --dearmor -o /usr/share/keyrings/caddy.gpg
sudo apt update && sudo apt install caddy

Caddyfile

example.com {
    reverse_proxy localhost:3000
}

Caddy automatically obtains and renews SSL certificates.