As a self-hosted enthusiast and a person who cares about green tech, I have recently started a journey to self host more and more of the services I use frequently.

At the last Open Source Summit Japan, I discovered PostmarketOS, a real Linux distribution for phones, which made me start experimenting with the possibilities reused hardware could bring to a more sustainable future.

In this talk, I strive to describe the process and approach I had to setup a reliable, resilient Kubernetes cluster using only old phones with PostmarketOS and k3s, as well as giving tips to find more sustainable uses for said technologies.