wget -O - https://packages.welsby.de/setup | sudo bash
curl -s https://packages.welsby.de/setup | sudo bash

Arch
----
/etc/pacman.conf:
[welsby]
SigLevel = Optional TrustAll
Server = https://packages.welsby.de

Ubuntu
------
/etc/apt/sources.list:
deb [trusted=yes] https://packages.welsby.de ./