#+title: Flake File Setup
#+setupfile: headers

* Flake File Setup
This configuration uses [[https://flake-file.denful.dev/][flake-file]]. This means my =flake.nix= file is
modular, as it allows me to define my inputs where I need them, and
not necessarily all at the same place. This can be a bit unusual for
people who are new to it, but trust me, it’s well worth it.

I’ll simply set up the outputs, a single one named =dendritic=, and the
description here, as nothing is too complicated.
#+begin_src nix :tangle yes
{
  <<inputs>>
  flake-file.outputs = "dendritic";
  flake-file.description = "NixOS and Home Manager configuration of P'undrak";
}
#+end_src

** Inputs
Some flake imputs are required globally, as they are used by default
by this configuration and some hosts.

#+name: inputs
#+begin_src nix
flake-file.inputs = {
  <<inputs-nixpkgs>>
  <<inputs-flake-parts>>
  <<inputs-flake-file>>
  <<inputs-import-tree>>
  <<inputs-home-manager>>
};
#+end_src

First, we get to nixpkgs, which
is quite necessary to get NixOS up and running: it gives access to
Nix’s packages. I also have a =nixpkgsStable= input for the kernel of my
PineTab 2 tablet. Otherwise, I use Nix unstable.

#+name: inputs-nixpkgs
#+begin_src nix
nixpkgsStable.url = "nixpkgs/nixos-25.11";
nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";
#+end_src

Next, I need some inputs for my dendritic config. =flake-parts= is the
heart of it: it’s a framework for writing flake modules that can
easily be put together as a single module defining an entire system,
such as a home configuration or a host configuration.
#+name: inputs-flake-parts
#+begin_src nix
flake-parts.url = "github:hercules-ci/flake-parts";
#+end_src

Next, we have flake-file, which permits the modularisation of my
=flake.nix= file itself, as mentioned abve.
#+name: inputs-flake-file
#+begin_src nix
flake-file.url = "github:vic/flake-file";
#+end_src

Next, we have =import-tree=, which automatically imports my Nix files,
making all modules globally known.
#+name: inputs-import-tree
#+begin_src nix
import-tree.url = "github:vic/import-tree";
#+end_src

And last but not least, =home-manager=. This allows me to manage the
programs of me as the user of my machine and not necessarily the
machine itself, as well as their configuration. As such, I can upgrade
a machine’s system without touching my environment, and the inverse is
true. However, it’s important to keep them in sync when it comes to
major upgrades of NixOS, so home-manager will follow the system’s
version.
#+name: inputs-home-manager
#+begin_src nix
home-manager = {
  url = "github:nix-community/home-manager";
  inputs.nixpkgs.follows = "nixpkgs";
};
#+end_src