diff --git a/advice.el b/advice.el
index 9e85ca8..e5f8255 100644
--- a/advice.el
+++ b/advice.el
@@ -1,20 +1,16 @@
 ;;; -*- lexical-binding: t; -*-
 (advice-add 'nix-straight-get-used-packages
             :before (lambda (&rest r)
-                      (message "Advising doom installer to gather packages to install...")
-                      (advice-add 'doom-reload-autoloads
+                      (message "[nix-doom-emacs] Advising doom installer to gather packages to install...")
+                      (advice-add 'doom-cli-reload-autoloads
                                   :override (lambda (&optional file force-p)
-                                              (message "Skipping generating autoloads...")))
+                                              (message "[nix-doom-emacs] Skipping generating autoloads...")))
                       (advice-add 'doom--format-print
                                   :around (lambda (orig-print &rest r)
                                             (let ((noninteractive nil))
                                               (apply orig-print r))))))
 
-
-
-(advice-add 'doom-call-process
-            :before (lambda (&rest r)
-                    (message "> call-process %s" r)))
-(advice-add 'doom-call-process
-            :after (lambda (&rest r)
-                    (message "< call-process %s" r)))
+(advice-add 'y-or-n-p
+            :override (lambda (q)
+                        (message "%s \n[nix-doom-emacs] --> answering NO" q)
+                        nil))
diff --git a/default.nix b/default.nix
index fb07c09..c53ec2e 100644
--- a/default.nix
+++ b/default.nix
@@ -1,7 +1,27 @@
 { # The files would be going to ~/.config/doom (~/.doom.d)
   doomPrivateDir
-  # Package set to install emacs and dependent packages from
+  /* Package set to install emacs and dependent packages from
+
+     Only used to get emacs package, if `bundledPackages` is set
+  */
 , emacsPackages
+  /* Use bundled revision of github.com/nix-community/emacs-overlay
+     as `emacsPackages`
+  */
+, bundledPackages ? true
+  /* Override dependency versions
+
+     Hadful for testing out updated dependencies without publishing
+     a new version of them.
+
+     Type: dependencyOverrides :: attrset -> either path derivation
+
+     Example:
+       dependencyOverrides = {
+         "emacs-overlay" = fetchFromGitHub { owner = /* ...*\/; };
+       };
+  */
+, dependencyOverrides ? { }
 , lib
 , pkgs
 , stdenv
@@ -14,6 +34,12 @@
 , writeTextDir }:
 
 let
+  lock = pkgs.callPackage
+    "${builtins.fetchTarball https://github.com/vlaci/nix-lock/archive/develop.tar.gz}/lock.nix" {
+      path = ./derivations.lock;
+      overrides = dependencyOverrides;
+    };
+
   # Packages we need to get the default doom configuration run
   overrides = self: super: {
     evil-escape = super.evil-escape.overrideAttrs (esuper: {
@@ -24,24 +50,14 @@ let
       version = "1";
       recipe = null;
       ename = pname;
-      src = fetchFromGitHub {
-        owner = "TobiasZawada";
-        repo = "org-yt";
-        rev = "40cc1ac76d741055cbefa13860d9f070a7ade001";
-        sha256 = "0jsm3azb7lwikvc53z4p91av8qvda9s15wij153spkgjp83kld3p";
-      };
+      src = lock.get pname;
     };
   };
 
   # Stage 1: prepare source for byte-compilation
   doomSrc = stdenv.mkDerivation {
     name = "doom-src";
-    src = fetchFromGitHub {
-      owner = "hlissner";
-      repo = "doom-emacs";
-      rev = "22ae9cca15f5aa9215cf0ec2c7b0b78d64deddc0";
-      sha256 = "0nya6qf2v0snd4zskxxradqdpiylpx3lxfrfi7xs04yb39ma99pn";
-    };
+    src = lock.get "doom-emacs";
     phases = ["unpackPhase" "patchPhase" "installPhase"];
     patches = [
       (substituteAll {
@@ -55,21 +71,24 @@ let
     '';
   };
 
+  # Bundled version of `emacs-overlay`
+  emacs-overlay = import (lock.get "emacs-overlay") pkgs pkgs;
+
   # Stage 2:: install dependencies and byte-compile prepared source
   doomLocal =
     let
-      straight-env = pkgs.callPackage (fetchFromGitHub {
-        owner = "vlaci";
-        repo = "nix-straight.el";
-        rev = "v1.0";
-        sha256 = "038dss49bfvpj15psh5pr9jyavivninl0rzga9cn8qyc4g2cj5i0";
-      }) {
-        emacsPackages = emacsPackages.overrideScope' overrides;
+      straight-env = pkgs.callPackage (lock.get "nix-straight.el") {
+        emacsPackages =
+          if bundledPackages then
+            let
+              epkgs = emacs-overlay.emacsPackagesFor emacsPackages.emacs;
+            in epkgs.overrideScope' overrides
+          else
+            emacsPackages.overrideScope' overrides;
         emacsLoadFiles = [ ./advice.el ];
         emacsArgs = [
+          "--"
           "install"
-          "--no-fonts"
-          "--no-env"
         ];
 
       # Need to reference a store path here, as byte-compilation will bake-in
diff --git a/derivations.json b/derivations.json
new file mode 100644
index 0000000..af276f9
--- /dev/null
+++ b/derivations.json
@@ -0,0 +1,20 @@
+{
+    "doom-emacs": {
+        "repo": "doom-emacs",
+        "owner": "hlissner",
+        "rev": "develop"
+    },
+    "nix-straight.el": {
+        "owner": "vlaci",
+        "repo": "nix-straight.el",
+        "rev": "v1.0"
+    },
+    "org-yt": {
+        "owner": "TobiasZawada",
+        "repo": "org-yt"
+    },
+    "emacs-overlay": {
+        "owner": "nix-community",
+        "repo": "emacs-overlay"
+    }
+}
diff --git a/derivations.lock b/derivations.lock
new file mode 100644
index 0000000..83ee68b
--- /dev/null
+++ b/derivations.lock
@@ -0,0 +1,54 @@
+{
+    "doom-emacs": {
+        "fetcher": "fetchFromGitHub",
+        "args": {
+            "owner": "hlissner",
+            "repo": "doom-emacs",
+            "rev": "58e674d8fb85515e7980c87fc708dabb2b276128",
+            "sha256": "1algblcah2y5lbrn60fjslszx3jz1p9w7bh82c788ih1d8x7z253"
+        },
+        "meta": {
+            "updated": "2019-11-10T14:33:52+00:00",
+            "rev": "58e674d8fb85515e7980c87fc708dabb2b276128"
+        }
+    },
+    "nix-straight.el": {
+        "fetcher": "fetchFromGitHub",
+        "args": {
+            "owner": "vlaci",
+            "repo": "nix-straight.el",
+            "rev": "6182914aefea06ef514cd3f3f7f9f67db45940db",
+            "sha256": "038dss49bfvpj15psh5pr9jyavivninl0rzga9cn8qyc4g2cj5i0"
+        },
+        "meta": {
+            "updated": "2019-10-25T22:28:25+00:00",
+            "rev": "6182914aefea06ef514cd3f3f7f9f67db45940db"
+        }
+    },
+    "org-yt": {
+        "fetcher": "fetchFromGitHub",
+        "args": {
+            "owner": "TobiasZawada",
+            "repo": "org-yt",
+            "rev": "40cc1ac76d741055cbefa13860d9f070a7ade001",
+            "sha256": "0jsm3azb7lwikvc53z4p91av8qvda9s15wij153spkgjp83kld3p"
+        },
+        "meta": {
+            "updated": "2019-10-25T22:28:27+00:00",
+            "rev": "40cc1ac76d741055cbefa13860d9f070a7ade001"
+        }
+    },
+    "emacs-overlay": {
+        "fetcher": "fetchFromGitHub",
+        "args": {
+            "owner": "nix-community",
+            "repo": "emacs-overlay",
+            "rev": "0bd32c063118ddc95d1a73ccd01b51a2d6dda24e",
+            "sha256": "1yc1az5l6073x1amk4g3rvfd98wsq3z3jvh2l7crp8q6wq9rndpa"
+        },
+        "meta": {
+            "updated": "2019-11-10T14:33:57+00:00",
+            "rev": "0bd32c063118ddc95d1a73ccd01b51a2d6dda24e"
+        }
+    }
+}
diff --git a/fix-paths.patch b/fix-paths.patch
index f6bcd81..145699f 100644
--- a/fix-paths.patch
+++ b/fix-paths.patch
@@ -1,25 +1,15 @@
-diff --git a/bin/doom b/bin/doom
-index bd381e5ab..37cc69569 100755
---- a/bin/doom
-+++ b/bin/doom
-@@ -6,7 +6,7 @@
- ":"; DOOMBASE=$(dirname "$0")/..
- ":"; [ "$1" = -d ] || [ "$1" = --debug ] && { shift; export DEBUG=1; }
- ":"; [ "$1" = doc ] || [ "$1" = doctor ] && { cd "$DOOMBASE"; shift; exec $EMACS --script bin/doom-doctor "$@"; exit 0; }
--":"; [ "$1" = run ] && { cd "$DOOMBASE"; shift; exec $EMACS -q --no-splash -l bin/doom "$@"; exit 0; }
-+":"; [ "$1" = run ] && { cd "$DOOMBASE"; shift; exec $EMACS -q --no-splash -l bin/.doom-wrapped "$@"; exit 0; }
- ":"; exec $EMACS --script "$0" -- "$@"
- ":"; exit 0
- 
 diff --git a/core/core.el b/core/core.el
-index 9cc1cfc25..fcbc3a3cf 100644
+index cb12f8d08..03f370691 100644
 --- a/core/core.el
 +++ b/core/core.el
-@@ -54,20 +54,20 @@ decrease this. If you experience stuttering, increase this.")
+@@ -63,22 +63,21 @@ decrease this. If you experience stuttering, increase this.")
+   "The root directory for Doom's modules. Must end with a slash.")
  
- (defvar doom-local-dir
-   (or (getenv "DOOMLOCALDIR")
--      (concat doom-emacs-dir ".local/"))
+ (defconst doom-local-dir
+-  (if-let (localdir (getenv "DOOMLOCALDIR"))
+-      (expand-file-name (file-name-as-directory localdir))
+-    (concat doom-emacs-dir ".local/"))
++  (or (getenv "DOOMLOCALDIR")
 +      "@local@/")
    "Root directory for local storage.
  
@@ -27,19 +17,19 @@ index 9cc1cfc25..fcbc3a3cf 100644
  These files should not be shared across systems. By default, it is used by
  `doom-etc-dir' and `doom-cache-dir'. Must end with a slash.")
  
--(defvar doom-etc-dir (concat doom-local-dir "etc/")
-+(defvar doom-etc-dir "~/.local/doom"
+-(defconst doom-etc-dir (concat doom-local-dir "etc/")
++(defconst doom-etc-dir "~/.local/doom"
    "Directory for non-volatile local storage.
  
  Use this for files that don't change much, like server binaries, external
  dependencies or long-term shared data. Must end with a slash.")
  
--(defvar doom-cache-dir (concat doom-local-dir "cache/")
-+(defvar doom-cache-dir "~/.cache/doom/"
+-(defconst doom-cache-dir (concat doom-local-dir "cache/")
++(defconst doom-cache-dir "~/.cache/doom/"
    "Directory for volatile local storage.
  
  Use this for files that change often, like cache files. Must end with a slash.")
-@@ -189,7 +189,7 @@ users).")
+@@ -196,7 +195,7 @@ users).")
  (setq abbrev-file-name             (concat doom-local-dir "abbrev.el")
        async-byte-compile-log-file  (concat doom-etc-dir "async-bytecomp.log")
        bookmark-default-file        (concat doom-etc-dir "bookmarks")