nix-doom-emacs/docs/reference.md

faq	readme	reference
docs/faq.md	README.md	this document

nix-doom-emacs reference

If you encounter any issues while using nix-doom-emacs, you can find some of us in the Matrix room. Only bugs should be filed in our issue tracker.

nix-doom-emacs uses nix-straight.el under the hood to install dependencies. It's a low level wrapper to integrate Nix with straight.el. It is maintained by the same people as this project.

Currently, nix-straight.el only extracts package names and uses emacs-overlay to obtain the package sources. This works most of the time but occasionally results in very obscure issues.

Getting Started

To get started, we suggest these methods. They are ordered from most suggested to least suggested. In all of these methods, you'll need your Doom Emacs configuration. It should contain the following three files: config.el, init.el and packages.el. If you don't already have an existing doom-emacs configuration, you can use the contents of test/doom.d as a template.

Home-Manager

With Flakes

File: flake.nix

{
  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable"
    home-manager.url = "github:nix-community/home-manager";
    nix-doom-emacs.url = "github:nix-community/nix-doom-emacs";
  };

  outputs = {
    self,
    nixpkgs,
    home-manager,
    nix-doom-emacs,
    ...
  }: {
    nixosConfigurations.exampleHost = nixpkgs.lib.nixosSystem {
      system  = "x86_64-linux";
      modules = [
        home-manager.nixosModules.home-manager
        {
          home-manager.users.exampleUser = { ... }: {
            imports = [ nix-doom-emacs.hmModule ];
            programs.doom-emacs = {
              enable = true;
              doomPrivateDir = ./doom.d; # Directory containing your config.el, init.el
                                         # and packages.el files
            };
          };
        }
      ];
    };
  };
}

Without Flakes

{ pkgs, ... }:

let
  doom-emacs = pkgs.callPackage (builtins.fetchTarball {
    url = https://github.com/nix-community/nix-doom-emacs/archive/master.tar.gz;
  }) {
    doomPrivateDir = ./doom.d;  # Directory containing your config.el, init.el
                                # and packages.el files
  };
in {
  home.packages = [ doom-emacs ];
}

NixOS

File: flake.nix

{
  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
    nix-doom-emacs.url = "github:nix-community/nix-doom-emacs";
  };
  
  outputs = {
    self,
    nixpkgs,
    nix-doom-emacs,
    ...
  }: {
    nixosConfigurations.exampleHost = nixpkgs.lib.nixosSystem {
      system  = "x86_64-linux";
      modules = [
        { 
          environment.systemPackages = 
            let
              doom-emacs = inputs.nix-doom-emacs.packages.${system}.defaut.override {
                doomPrivateDir = ./doom.d;
              };
            in [
              doom-emacs
            ];
        }
        # ...
      ];
    };
  };
}

For what it's worth, you can see all overridable parameters of nix-doom-emacs in default.nix.

Standalone

Flake

{
  description = "nix-doom-emacs shell";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
    nix-doom-emacs.url = "github:nix-community/nix-doom-emacs";
  };

  outputs = { self, nixpkgs, nix-doom-emacs, ... }:
  let
    system = "x86_64-linux";
    pkgs = import nixpkgs { inherit system; };
    doom-emacs = nix-doom-emacs.packages.${system}.default.override {
      doomPrivateDir = ./doom.d;
    };
  in
  {
    devShells.${system}.default = pkgs.mkShell {
      buildInputs = [ doom-emacs ];
    };
  };
}

Non-Flake

{ pkgs ? import <nixpkgs> { } }:

let
  repo = pkgs.fetchFromGitHub {
    owner = "nix-community";
    repo = "nix-doom-emacs";
    rev = "<commit>";
    sha256 = "<hash>";
  };
  nix-doom-emacs = pkgs.callPackage (import repo) {
    doomPrivateDir = ./doom.d;
  };
in
pkgs.mkShell {
  buildInputs = [ nix-doom-emacs ];
}

Setup

Emacs daemon

If you use the Home-Manager module, you can enable it via services.emacs.enable = true;. The Home-Manager module will do the rest for you.

If you're not, and you're using a standalone method (NixOS only without home-manager/nix-darwin) instead, you'll need:

services.emacs = {
  enable = true;
  package = inputs.doom-emacs.packages.${system}.doom-emacs.override {
    doomPrivateDir = ./doom.d;
  };
};

You can now run emacsclient -c to connect to the daemon.

Custom Emacs derivations (i.e., pgtk, nativeComp)

You can use the emacsPackage attribute after applying emacs-overlay to your Nixpkgs:

programs.doom-emacs =   {
  enable = true;
  doomPrivateDir = ./doom.d;
  emacsPackage = pkgs.emacsPgtkNativeComp;
}

For Non-HM:

let
  # ...
  doom-emacs = nix-doom-emacs.packages.${system}.default.override {
    doomPrivateDir = ./doom.d;
    emacsPackage = pkgs.emacsPgtkNativeComp;
  };
in {
  # ...
}

And for Non-Flake:

let
  # ...
  nix-doom-emacs = pkgs.callPackage (import repo) {
    doomPrivateDir = ./doom.d;
    emacsPackage = pkgs.emacsPgtkNativeComp
  };
in {
  # ...
}

trivialBuild and co

Though beyond the scope of this document, trivialBuild is a Nixpkgs function to trivially build Emacs packages, if you're confused about it's usage here. You can use it to build e.g. local packages or packages hosted on Git repositories. It is not a nix-doom-emacs tool. It's also in a family of functions in Nixpkgs which are made to build Emacs packages. Such as:

generic: This is the "base" function which all the other build functions are derived from.

elpaBuild, and melpaBuild: Those are self-explanatory. To find examples of how they're used, you'll unfortunately have to search Nixpkgs for them. Luckily, the way they're used in Nixpkgs is very simple.