dippy

dippy is at its core a custom NixOS deployment tool built for the needs of my personal homelab.

Over time, it gained some additional responsibilities, but the goal of running this homelab is the common thread.

Before I wrote dippy, I was using colmena to deploy my NixOS hosts, but I wanted my own tool to be able to add features that I wanted that I did not expect others to care about. At the time, I wanted to be able to define staged phases for my deploys without having to make multiple calls to colmena (which would require multiple Nix evaluations). And once I had my own tool, I could (and have) customize it to whatever I needed.

=> colmena: A simple, stateless NixOS deployment tool
=> dippy's source code

What does dippy do?

• Build NixOS systems locally and deploy them to remote hosts
• Compare a built NixOS system to what's currently running on the machine (a la nvd)
• Push built NixOS systems to an attic cache
• Check service health in Consul after successful system activation
• Build the local system, show a diff, and prompt for confirmation before activating
• Use switch inhibitors to determine whether to apply changes in-place or after a reboot
• Reboot a remote system and wait for it to come back up
• Diff and apply infrastructure changes using Pulumi
• Maintain forks of dependencies to keep them current with upstream changes
• Bootstrap new microVMs in the lab by generating Nix code and updating necessary systems

That's a lot of responsibilities! Probably too many for a tool meant for general use, but since it's just for me, it's whatever.