branjam4 / muffin-base

A guix channel for custom OS flavors to build on.

Muffin Base

Introduction

With Guix System, I’ve been working on a setup that will reproduce my home and system configuration on a diskless computer. After accomplishing this I went back and forth between initiating the system from the server and upgrading it from the client. I copied and maintained the entire system configuration on both machines, in a way that introduced friction whenever I refactored the system or introduced a new feature.

So I defined base operating system templates that I can inherit from and then fill in with the more specific settings (e.g. where the bootloader and root fs are). Incorporating it into a channel to take advantage of guix infrastructure is icing on top!

Adding the channel

Add the (channel ...) record for this repo to a channels.scm file for guix.

Example:

(channel
 (name 'your-name-for-this-channel)
 (url "https://github.com/branjam4/muffin-base.git")
 (branch "main")
 (introduction
  (make-channel-introduction
   "c98b84faada9d373fdc6a189a41e8f54c59354c8"
   (openpgp-fingerprint
    "DC82 E7A3 8F7F CDED 4FC4  2913 628E CE8F AEB0 3809"))))

Example channels.scm:

(append '((channel
	     (name 'bran-muffin)
	     (url "https://github.com/branjam4/muffin-base.git")
	     (branch "main")
	     (introduction
	      (make-channel-introduction
	       "c98b84faada9d373fdc6a189a41e8f54c59354c8"
	       (openpgp-fingerprint
		"DC82 E7A3 8F7F CDED 4FC4  2913 628E CE8F AEB0 3809")))))
	  %default-channels)

Then either:

1. Place it where guix reads channel info by default (e.g. ~/.config/guix/channels.scm) and run guix pull, or
2. Run guix pull -C /path/to/other/channels.scm.

Using the channel

muffin.scm has sample records which represent data you’d want to use across operating system definitions, or overrides for what is there by default.

Here’s an example config.scm based on my own setup:

 (use-modules (gnu)
	       (gnu services)
	       (gnu services admin)	 ; hosts-service-type
	       (gnu system accounts)	 ; for (user-account) record
	       (gnu system file-systems) ; for (file-systems) record
	       (muffin system images net)) ; %muffin-net-layer OS templ.

 (define branjam
   (user-account
    (name "branjam")
    (group "users")
    (supplementary-groups
     '("audio" "video" "netdev" "input"
	"wheel")) ; wheel to make this an account admin
    ;; the other fields (redacted): home-directory, password, comment
    (...)))

 (define %my-server-file-systems ...)
 (define %my-net-file-systems ...)

 (define %muffin-os
   (operating-system
     (inherit %muffin-net-layer)
     (host-name "branmuffin")
     (timezone "Etc/UTC") ; your timezone here
     (users (cons*
	      branjam
	      (operating-system-users %muffin-net-layer)))
     (services
      (append
	(list
	 (simple-service 'add-extra-hosts
			 hosts-service-type
			 (list (host "10.0.0.1" "serverhostname"))))
	(operating-system-user-services %muffin-net-layer)))
     (file-systems %bran-net-file-systems)))

 %muffin-os

Why use this?

Overall, I’d recommend subscribing to the popular channels with more battle-tested configuration approaches.

But if this repo’s approach to configuration provides a promising template to customizing your own system, you can borrow from modules like (muffin system images net) by adding the channel to a channels.scm file (shown above). It may be especially useful assuming you have machines similar to mine (x86 systems) and would like to scrutinize how I’ve set up network boot with Guix System.

Or, alternatively, you may be interested in particular packages or services here not available in other channels.