My personal Nix system config

This is my personal Nix system configuration. Mostly I use this to manage my environments for my Mac systems using nix-darwin; however, I have also experimented with creating developer NixOS VMs that run on Parallels (see below).

Generally speaking, the configuration of the host and home environment are separated such that we can define, build and apply these configs separately.I find that I need to more frequently update home configs that host configs, so I think it's useful to separate them.

These configs use Nix flakes.

The structure of this repo was inspired by the excellent Misterio77/nix-config repo, though the two repos have subsequently diverged.

TLDR Getting started

Install Nix:

sh <(curl -L https://nixos.org/nix/install)

Note: this has only really been tested for multi-user installation.

Enable flakes:

echo "experimental-features = nix-command flakes" > ~/.config/nix/nix.conf

Bootstrap/install nix-darwin and home-manager:

nix-darwin:

nix-build https://github.com/LnL7/nix-darwin/archive/master.tar.gz -A installer
./result/bin/darwin-installer

home-manager (standalone):

nix-channel --add https://github.com/nix-community/home-manager/archive/master.tar.gz home-manager
nix-channel --update
nix-shell '<home-manager>' -A install

Clone this repo:

git clone git@github.com:keithschulze/nixos-config.git

Build and apply host config

darwin-rebuild switch --flake .#matawhero

note: in this case we are applying the matawhero host configuration as an example. Other hosts are/can be defined in flake.nix.

Build and apply the home configuration

home-manager switch --flake .#keithschulze@matawhero

note: in this case we are applying the keithschulze@matawhero home configuration as an example. Other home configrations are/can be defined in flake.nix.

Updating

In order to update packages, we need to update the locked versions:

nix flake update

Before applying or committing this, we should check that it builds correctly with update versions:

darwin-rebuild build --flake .#matawhero
home-manager build --flake .#keithschulze@matawhero

Note: this example only builds host and home configs for a single host and user. We should do this for all that matter.

Parallels developer VM setup [no actively used]

This is my NixOS Parallels developer VM setup. This is adapted from Mitchell Hashimoto's excellent NixOS VM repo.

Setup

If you need an ISO for NixOS, you can build your own in the iso folder. For x86-64, I usually just download the official ISO, but I build the ISO from scratch for aarch64. There is a make target iso/nixos.iso you can use for building an ISO. You'll also need a docker running on your machine for building an ISO.

$ make iso/nixos.iso

Create a Parallels VM with the following settings:

ISO: NixOS 21.05 or later.
Disk: SATA 150 GB+
CPU/Memory: I give at least half my cores and half my RAM, as much as you can.
Graphics: Full acceleration, full resolution, maximum graphics RAM.
Network: Shared with my Mac.
Remove sound card, remove video camera.
Profile: Disable almost all keybindings

Boot the VM, and using the graphical console, change the root password to "root":

$ sudo su
$ passwd
# change to root

Run ifconfig and get the IP address of the first device. It is probably 192.168.58.XXX, but it can be anything. In a terminal with this repository set this to the NIXADDR env var:

$ export NIXADDR=<VM ip address>

Perform the initial bootstrap. This will install NixOS on the VM disk image but will not setup any other configurations yet. This prepares the VM for any NixOS customization:

$ make vm/bootstrap0

After the VM reboots, this is usually a good time to take a VM Snapshot because you might want to return to this point while you stuff around with configs. Run the full bootstrap, this will finalize the NixOS customization using this configuration:

$ make vm/bootstrap

At this point, the core will be setup; however, you still need to run home-manager to setup the full Desktop environment. Boot the VM and jump into /nix-config. Run nix develop and then home-manager switch --flake .