This is a hard coded value to a specific mirror, which doesn't CDN to the user's nearest endpoint and there's no guarantee's it'll be up. I propose switching to mirror.archlinuxarm.org not de3.mirror.archlinuxarm.org.
Contrary to popular belief, using a common mirror point is unreliable. You are interested in geography, not in the mirror's workload. Because of this, I removed this and use a specific mirror.
This is a hard coded value to a specific mirror, which doesn't CDN to the user's nearest endpoint and there's no guarantee's it'll be up. I propose switching to mirror.archlinuxarm.org not de3.mirror.archlinuxarm.org.
Here's the line's with issues: https://github.com/pikvm/os/blob/8af3a5fe1f8c2653cb29d6a49778c1eb24e5f848/Makefile#L10-L11
I'll experiment today to see if it works, and submit a PR for this.