Emacs overlay for Nixpkgs

Contents of the overlay

Elpa

Daily generations of Elpa.

Melpa / Melpa stable

Daily generations of Melpa & Melpa stable attribute sets.

EXWM & needed dependencies

This overlay provides fresh versions of EXWM and dependencies. This is updated daily.

Emacs from Git and latest (including pre-releases)

This overlay also provides two versions (latest from git) for Emacs. These are updated daily.

These attributes are named emacsGit and emacsUnstable. emacsGit is built from the latest master branch and emacsUnstable is built from the latest tag.

Emacs from git is not guaranteed stable and may break your setup at any time, if it breaks you get to keep both pieces.

The feature/native-comp branch is also provided under the attribute emacsGcc. This is to be considered highly experimental.

We also provide two attributes named emacsGit-nox and emacsUnstable-nox if you wish to have Emacs built without X dependencies.

Extra library functionality

This overlay comes with extra functions to generate an Emacs closure from various types of dependency declaration. (These are abstractions on top of emacsWithPackages.)

For example, emacsWithPackagesFromUsePackage adds packages which are required in a user’s config via use-package:

{
  environment.systemPackages = [
    (emacsWithPackagesFromUsePackage {
      config = builtins.readFile ./emacs.el;
      # Package is optional, defaults to pkgs.emacs
      package = pkgs.emacsGit;
      # Optionally provide extra packages not in the configuration file
      extraEmacsPackages = epkgs: [
        epkgs.cask
      ];
      # Optionally override derivations
      override = epkgs: epkgs // {
        weechat = epkgs.melpaPackages.weechat.overrideAttrs(old: {
          patches = [ ./weechat-el.patch ];
        });
      };
    })
  ];
}

Similarly, emacsWithPackagesFromPackageRequires adds packages which are declared in a .el package file’s Package-Requires header, which can be handy for CI purposes:

...
let
  emacsForCI = pkgs.emacsWithPackagesFromPackageRequires {
    packageElisp = builtins.readFile ./flycheck.el;
    extraEmacsPackages = epkgs: [
      epkgs.package-lint
    ];
  };
pkgs.mkShell {
  buildInputs = [ emacsForCI ];
}

Usage of the overlay

Latest master each rebuild

One way, and probably the most convenient way to pull in this overlay is by just fetching the tarball of latest master on rebuild.

This has side-effects if packages breaks or things like that you may want to be in control of which revision of the overlay you run.

Adding the overlay this way will extend your Emacs packages set to contain the latest EXWM and dependencies from their respective master and make the package emacsGit available. These of course change quite rapidly and will cause compilation time.

{
  nixpkgs.overlays = [
    (import (builtins.fetchTarball {
      url = https://github.com/nix-community/emacs-overlay/archive/master.tar.gz;
    }))
  ];
}

Community

IRC

#nixos-emacs on freenode

Nixpkgs issues

Emacs tracking issue

NixOS/nixpkgs#66303

matthuszagh/emacs-overlay