Install NixOS on a Free Oracle Cloud VM

Oracle is not a very popular cloud hosting service, but they have an unusually attractive free tier offering. You can run the following two VMs for free 24/7:

4 CPU / 24 GB RAM Ampere A1 ARM VM
1 CPU / 1 GB RAM AMD CPU

The AMD one is not that exciting, but a 4-CPU / 24 GB system is more powerful than you’ll find in the free tier of any other cloud vendor.