~/.doom.d no longer needs to be installed

`extraConfig` is merged into doom user's `config.el` file

README.md

@@ -19,14 +19,13 @@ Using [home-manager](https://github.com/rycee/home-manager):
 { pkgs, ... }:
 
 let
-  doomPrivateDir = ./doom.d;
-
   doom-emacs = pkgs.callPackage (builtins.fetchTarball {
     url = https://github.com/vlaci/nix-doom-emacs/archive/master.tar.gz;
-  }) { inherit doomPrivateDir; };
+  }) {
+    doomPrivateDir = ./doom.d;
+  };
 in {
   home.packages = [ doom-emacs ];
-  home.file.".doom.d".source = doomPrivateDir;
   home.file.".emacs.d".source = doom-emacs.emacsd;
 }
 ```

default.nix

@@ -142,9 +142,8 @@ let
       packages = straight-env.packageList (super: {
         phases = [ "installPhase" ];
         preInstall = ''
-          export DOOMDIR=$(mktemp -d)
-          export DOOMLOCALDIR=$DOOMDIR/local/
-          cp ${doomPrivateDir}/* $DOOMDIR
+          export DOOMDIR=${doomPrivateDir}
+          export DOOMLOCALDIR=$(mktemp -d)/local/
         '';
       });
 
@@ -160,10 +159,8 @@ let
       phases = [ "installPhase" ];
       buildInputs = super.buildInputs ++ [ git ];
       preInstall = ''
-          export DOOMDIR=$(mktemp -d)
+          export DOOMDIR=${doomPrivateDir}
           export DOOMLOCALDIR=$out/
-          mkdir -p $DOOMDIR
-          cp ${doomPrivateDir}/* $DOOMDIR
       '';
     });
 
@@ -196,20 +193,26 @@ let
       (load "${doom-emacs}/init.el")
     '';
 
-    load-extra-config = writeTextDir "share/emacs/site-lisp/nix-integration.el" ''
-      ;;; -*- lexical-binding: t; -*-
-
-      ${extraConfig}
+    # `extraConfig` is merged into private configuration
+    doomDir = pkgs.runCommand "doom-private" {
+      inherit extraConfig;
+      passAsFile = [ "extraConfig" ];
+    } ''
+        mkdir -p $out
+        cp ${doomPrivateDir}/* $out
+        chmod u+w $out/config.el
+        cat $extraConfigPath >> $out/config.el
     '';
   in (emacsPackages.emacsWithPackages (epkgs: [
-    load-extra-config
     load-config-from-site
   ])).overrideAttrs (super: {
     outputs = [ "out" "emacsd" ];
     buildInputs = [ doom-emacs ];
     installPhase = super.installPhase + ''
-      echo ln -snf ${doom-emacs} $emacsd
       ln -snf ${doom-emacs} $emacsd
+      for prog in $out/bin/*; do
+        wrapProgram $prog  --set DOOMDIR ${doomDir}
+      done
     '';
   });
 

nix-integration.patch

@@ -38,11 +38,3 @@ index cb12f8d08..03f370691 100644
        custom-theme-directory       (concat doom-private-dir "themes/")
        desktop-dirname              (concat doom-etc-dir "desktop")
        desktop-base-file-name       "autosave"
-@@ -489,6 +488,7 @@ to least)."
-                    (daemonp))
-                (file-exists-p doom-env-file))
-       (doom-load-envvars-file doom-env-file))
-+    (load "nix-integration.el" t)
- 
-     (require 'core-modules)
-     (let (;; `doom-autoload-file' tells Emacs where to load all its functions