A simple bash script that installs caddy as a service on your Linux system, merely automating the official steps described here https://caddyserver.com/docs/install#linux-service

caddy-linux-service.sh

#!/bin/bash

echo "Enter your download url that you made from here: https://caddyserver.com/download"
read downloadurl

curl --output caddy $downloadurl

chmod +x caddy
sudo mv caddy /usr/bin

# Confirmation dialogue taken from https://stackoverflow.com/a/1885534/5522348
read -p "Do you want to allow caddy to use low-level ports? (E.g. 80 and 443) [y/N]"
echo
if [[ $REPLY =~ ^[Yy]$ ]]
then
  sudo setcap 'cap_net_bind_service=+ep' /usr/bin/caddy
fi

sudo groupadd --system caddy
sudo useradd --system \
    --gid caddy \
    --create-home \
    --home-dir /var/lib/caddy \
    --shell /usr/sbin/nologin \
    --comment "Caddy web server" \
    caddy

curl --output caddy.service https://raw.githubusercontent.com/caddyserver/dist/master/init/caddy.service
sudo mv caddy.service /etc/systemd/system/caddy.service

sudo systemctl daemon-reload
sudo systemctl enable caddy

sudo mkdir /etc/caddy/

echo "Done! Now just create a Caddyfile and put it in /etc/caddy/Caddyfile"
echo "Then, simple run the following command to start the caddy service:"
echo "sudo systemctl start caddy"
echo "Logs are available through the following command:"
echo "journalctl -u caddy --no-pager | less"
echo "Reload (to apply configuration changes if need be) and stop caddy with the following commands respectively"
echo "sudo systemctl reload caddy"
echo "sudo systemctl stop caddy"
echo "Have a nice day!"