Generations are linear, so if you are on 6, roll back to 3, and make a new change (I'm 90% sure) it will create 7. I've used NixOS a liiiiitle bit on a laptop

Generations are linear, so if you are on 6, roll back to 3, and make a new change (I'm 90% sure) it will create 7. I've used NixOS a liiiiitle bit on a laptop but not enough to really get into it. We're toying with the idea of exploring supporting NixOS as a primary local development environment (and a host for cloud-based development environments) but there's lot of work to do to make that work well.