Make Emacs flake standalone

flake.lock

@@ -66,9 +66,6 @@
     },
     "emacsConfig": {
       "inputs": {
-        "home-manager": [
-          "home-manager"
-        ],
         "nixpkgs": [
           "nixpkgs"
         ]

flake.nix

@@ -32,7 +32,6 @@
     emacsConfig = {
       url = "path:./flakes/emacs";
       inputs.nixpkgs.follows = "nixpkgs";
-      inputs.home-manager.follows = "home-manager";
     };
   };
 

flakes/emacs/README.md

@@ -0,0 +1,54 @@
+# Tobmacs flake
+
+This flake builds the complete Emacs configuration without Home Manager. It
+contains Emacs, all Emacs packages, tree-sitter grammars, snippets, Hunspell,
+and dictionaries.
+
+## Run or install directly
+
+```console
+nix run 'git+https://codeberg.org/oibot/dotfiles?dir=flakes/emacs'
+nix profile install 'git+https://codeberg.org/oibot/dotfiles?dir=flakes/emacs'
+```
+
+From this repository, use `nix run path:./flakes/emacs`.
+
+## NixOS
+
+Add the flake as an input and make its nixpkgs follow the system nixpkgs:
+
+```nix
+{
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    tobs-emacs = {
+      url = "git+https://codeberg.org/oibot/dotfiles?dir=flakes/emacs";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+  };
+
+  outputs = { nixpkgs, tobs-emacs, ... }: {
+    nixosConfigurations.server = nixpkgs.lib.nixosSystem {
+      system = "x86_64-linux";
+      modules = [
+        tobs-emacs.nixosModules.default
+        {
+          # Installs Tobmacs and starts an Emacs user service. No Home Manager
+          # module is involved.
+          services.emacs.enable = true;
+          services.emacs.startWithGraphical = false;
+        }
+      ];
+    };
+  };
+}
+```
+
+If no daemon is wanted, either set `services.emacs.install = true` instead of
+`enable`, or install the package directly:
+
+```nix
+environment.systemPackages = [
+  tobs-emacs.packages.${pkgs.stdenv.hostPlatform.system}.default
+];
+```

flakes/emacs/flake.lock

@@ -0,0 +1,27 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1784120854,
+        "narHash": "sha256-KesHgItiZPgGX740axSiQLcIQ8D24MDqNpkKYWIek8k=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "753cc8a3a87467296ddd1fa93f0cc3e81120ee46",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flakes/emacs/flake.nix

@@ -1,15 +1,55 @@
 {
-  inputs = {
-    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
-    home-manager.url = "github:nix-community/home-manager/";
-    home-manager.inputs.nixpkgs.follows = "nixpkgs";
-  };
+  description = "Standalone Tobmacs package and NixOS integration";
 
-  outputs = inputs:
+  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+
+  outputs = { self, nixpkgs }:
+    let
+      systems = [
+        "aarch64-darwin"
+        "aarch64-linux"
+        "x86_64-linux"
+      ];
+      forAllSystems = nixpkgs.lib.genAttrs systems;
+    in
     {
+      packages = forAllSystems (system:
+        let
+          pkgs = import nixpkgs {
+            inherit system;
+            config.allowUnfreePredicate = package:
+              builtins.elem (nixpkgs.lib.getName package) [
+                "copilot-language-server"
+              ];
+          };
+        in
+        {
+          default = import ./package.nix { inherit pkgs; };
+          tobs-emacs = self.packages.${system}.default;
+        });
+
+      apps = forAllSystems (system: {
+        default = {
+          type = "app";
+          program = "${self.packages.${system}.default}/bin/emacs";
+          meta.description = "Run Tobmacs";
+        };
+      });
+
+      # Importing this module selects Tobmacs as services.emacs.package. The
+      # caller still decides whether to enable or merely install the service.
+      nixosModules.default = { pkgs, ... }: {
+        services.emacs.package =
+          self.packages.${pkgs.stdenv.hostPlatform.system}.default;
+      };
+
+      # Optional compatibility integration for this dotfiles repository. The
+      # standalone package and NixOS module above do not depend on Home Manager.
       homeManagerModules = {
-        aarch64-darwin = import ./home.nix;
-        x86_64-linux = import ./home.nix;
+        default = import ./home.nix { inherit self; };
+        aarch64-darwin = self.homeManagerModules.default;
+        aarch64-linux = self.homeManagerModules.default;
+        x86_64-linux = self.homeManagerModules.default;
       };
     };
 }

flakes/emacs/home.nix

@@ -1,125 +1,17 @@
-{ config, pkgs, lib, ... }:
+{ self }:
+{ pkgs, lib, ... }:
 let
-  treeSitterLibraryExtension =
-    if pkgs.stdenv.hostPlatform.isDarwin then "dylib" else "so";
-
-  treeSitterGrammars = {
-    swift = pkgs.tree-sitter-grammars.tree-sitter-swift;
-    python = pkgs.tree-sitter-grammars.tree-sitter-python;
-    typescript = pkgs.tree-sitter-grammars.tree-sitter-typescript;
-    tsx = pkgs.tree-sitter-grammars.tree-sitter-tsx;
-    javascript = pkgs.tree-sitter-grammars.tree-sitter-javascript;
-    json = pkgs.tree-sitter-grammars.tree-sitter-json;
-  };
+  emacs = self.packages.${pkgs.stdenv.hostPlatform.system}.default;
 in
 {
-  home.packages = with pkgs; [
-    enchant
-    hunspell
-    hunspellDicts.de_DE
-    hunspellDicts.en_US
-  ];
+  home.packages = [ emacs ];
 
-  home.file =
-    (lib.mapAttrs'
-      (language: grammar:
-        lib.nameValuePair
-          ".emacs.d/tree-sitter/libtree-sitter-${language}.${treeSitterLibraryExtension}"
-          { source = "${grammar}/parser"; })
-      treeSitterGrammars)
-    // {
-      ".emacs.d/early-init.el".source = ./config/early-init.el;
-      ".emacs.d/snippets".source = ./config/snippets;
-    };
-
-  programs.emacs = {
-    enable = true;
-    extraConfig = builtins.readFile ./config/init.el +
-      builtins.readFile ./config/lisp/utils.el;
-    extraPackages = epkgs:
-      let
-        myEpkgs = epkgs.overrideScope (import ./pkgs { inherit pkgs; });
-      in
-      with myEpkgs; [
-        agent-shell
-        apheleia
-        avy
-        cape
-        catppuccin-theme
-        cider
-        clojure-mode
-        consult
-        consult-denote
-        copilot
-        corfu
-        denote
-        diff-hl
-        dockerfile-mode
-        ef-themes
-        eglot
-        envrc
-        exec-path-from-shell
-        flycheck
-        flycheck-clj-kondo
-        flycheck-swiftlint
-        flymake-collection
-        git-timemachine
-        graphql-mode
-        helpful
-        htmlize
-        jinx
-        js2-mode
-        json-mode
-        ledger-mode
-        ligature
-        markdown-mode
-        minions
-        multiple-cursors
-        nerd-icons
-        nerd-icons-completion
-        nerd-icons-corfu
-        nerd-icons-dired
-        nerd-icons-ibuffer
-        ob-restclient
-        ob-swift
-        olivetti
-        orderless
-        org
-        org-modern
-        ox-gfm
-        ox-reveal
-        pulsar
-        rainbow-delimiters
-        rainbow-mode
-        restclient
-        smartparens
-        swift-mode
-        swift-ts-mode
-        super-save
-        terraform-mode
-        treesit-auto
-        ob-typescript
-        yaml-mode
-        vterm
-        fontaine
-        magit
-        magit-todos
-        marginalia
-        modus-themes
-        nix-mode
-        vertico
-        web-mode
-        winpulse
-        yasnippet
-      ];
-  };
-
-  launchd.agents.emacs-server = {
+  launchd.agents.emacs-server = lib.mkIf pkgs.stdenv.hostPlatform.isDarwin {
     enable = true;
     config = {
       KeepAlive = true;
       ProgramArguments = [
-        "${config.programs.emacs.finalPackage}/bin/emacs"
+        "${emacs}/bin/emacs"
         "--fg-daemon"
       ];
       RunAtLoad = true;

flakes/emacs/package.nix

@@ -0,0 +1,158 @@
+{ pkgs }:
+let
+  inherit (pkgs) lib;
+
+  treeSitterLibraryExtension =
+    if pkgs.stdenv.hostPlatform.isDarwin then "dylib" else "so";
+
+  treeSitterGrammars = {
+    swift = pkgs.tree-sitter-grammars.tree-sitter-swift;
+    python = pkgs.tree-sitter-grammars.tree-sitter-python;
+    typescript = pkgs.tree-sitter-grammars.tree-sitter-typescript;
+    tsx = pkgs.tree-sitter-grammars.tree-sitter-tsx;
+    javascript = pkgs.tree-sitter-grammars.tree-sitter-javascript;
+    json = pkgs.tree-sitter-grammars.tree-sitter-json;
+  };
+
+  treeSitterBundle = pkgs.runCommand "tobmacs-tree-sitter-grammars" { } (
+    ''
+      mkdir -p "$out/lib"
+    ''
+    + lib.concatStringsSep "\n" (lib.mapAttrsToList
+      (language: grammar: ''
+        ln -s "${grammar}/parser" \
+          "$out/lib/libtree-sitter-${language}.${treeSitterLibraryExtension}"
+      '')
+      treeSitterGrammars)
+  );
+
+  epkgs = (pkgs.emacsPackagesFor pkgs.emacs).overrideScope (
+    import ./pkgs { inherit pkgs; }
+  );
+
+  emacsPackages = with epkgs; [
+    agent-shell
+    apheleia
+    avy
+    cape
+    catppuccin-theme
+    cider
+    clojure-mode
+    consult
+    consult-denote
+    copilot
+    corfu
+    denote
+    diff-hl
+    dockerfile-mode
+    ef-themes
+    eglot
+    envrc
+    exec-path-from-shell
+    flycheck
+    flycheck-clj-kondo
+    flycheck-swiftlint
+    flymake-collection
+    fontaine
+    git-timemachine
+    graphql-mode
+    helpful
+    htmlize
+    jinx
+    js2-mode
+    json-mode
+    ledger-mode
+    ligature
+    magit
+    magit-todos
+    marginalia
+    markdown-mode
+    minions
+    modus-themes
+    multiple-cursors
+    nerd-icons
+    nerd-icons-completion
+    nerd-icons-corfu
+    nerd-icons-dired
+    nerd-icons-ibuffer
+    nix-mode
+    ob-restclient
+    ob-swift
+    ob-typescript
+    olivetti
+    orderless
+    org
+    org-modern
+    ox-gfm
+    ox-reveal
+    pulsar
+    rainbow-delimiters
+    rainbow-mode
+    restclient
+    smartparens
+    super-save
+    swift-mode
+    swift-ts-mode
+    terraform-mode
+    treesit-auto
+    vertico
+    vterm
+    web-mode
+    winpulse
+    yaml-mode
+    yasnippet
+  ];
+
+  configDirectory = pkgs.runCommand "tobmacs-config" { } ''
+    mkdir -p "$out"
+    cp ${./config/early-init.el} "$out/early-init.el"
+    cat > "$out/init.el" <<'EOF'
+    ;; -*- lexical-binding: t; -*-
+
+    ;; --init-directory points at the immutable Nix store. Reset this after
+    ;; startup has found init.el so mutable state remains in the user's home.
+    (setq user-emacs-directory (expand-file-name "~/.emacs.d/"))
+    (make-directory user-emacs-directory t)
+    (setq yas-snippet-dirs '("${./config/snippets}"))
+
+    ${builtins.readFile ./config/init.el}
+    ${builtins.readFile ./config/lisp/utils.el}
+    EOF
+  '';
+
+  emacsWithPackages = epkgs.emacsWithPackages (
+    _: emacsPackages ++ [ treeSitterBundle ]
+  );
+
+  # Make this package own its init directory, including a real early-init.el.
+  # The inner emacsWithPackages wrapper still supplies all package load paths.
+  emacs = pkgs.symlinkJoin {
+    name = "tobmacs-emacs";
+    paths = [ emacsWithPackages ];
+    nativeBuildInputs = [ pkgs.makeBinaryWrapper ];
+    postBuild = ''
+      wrapProgramBinary "$out/bin/emacs" \
+        --add-flags "--init-directory=${configDirectory}"
+
+      if [ -x "$out/Applications/Emacs.app/Contents/MacOS/Emacs" ]; then
+        wrapProgramBinary "$out/Applications/Emacs.app/Contents/MacOS/Emacs" \
+          --add-flags "--init-directory=${configDirectory}"
+      fi
+    '';
+    meta = emacsWithPackages.meta;
+  };
+in
+pkgs.buildEnv {
+  name = "tobmacs";
+  paths = [
+    emacs
+    pkgs.enchant
+    pkgs.hunspell
+    pkgs.hunspellDicts.de_DE
+    pkgs.hunspellDicts.en_US
+  ];
+  meta = emacs.meta // {
+    description = "Emacs with Tobias Ostner's configuration and packages";
+    mainProgram = "emacs";
+  };
+}