diff --git a/.github/flake.lock b/.github/flake.lock
index 7e34aff..bfb7ee5 100644
--- a/.github/flake.lock
+++ b/.github/flake.lock
@@ -11,11 +11,11 @@
         "nixpkgs-stable": "nixpkgs-stable"
       },
       "locked": {
-        "lastModified": 1697857699,
-        "narHash": "sha256-VGtcRMKi3w1hsPKduOqiSLVnSX1nO/2oixHV7mlVLFw=",
+        "lastModified": 1704243594,
+        "narHash": "sha256-J2ZteH4bGbkTbrmLhEra8Lh3Su8bDoKA0a0Y+lUb3cc=",
         "owner": "nix-community",
         "repo": "emacs-overlay",
-        "rev": "e58f332cc035aaaf82c9c9f8e07b3e21ac977d77",
+        "rev": "ac761af646d27dade521104de298dd4a7032c508",
         "type": "github"
       },
       "original": {
@@ -41,32 +41,32 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1688392541,
-        "narHash": "sha256-lHrKvEkCPTUO+7tPfjIcb7Trk6k31rz18vkyqmkeJfY=",
+        "lastModified": 1704263837,
+        "narHash": "sha256-2aHlly9qfqgvN83yA9M86CtvOITn3V2+BymsPchMJ9I=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "ea4c80b39be4c09702b0cb3b42eab59e2ba4f24b",
+        "rev": "a2103ac8a71bfff2b72f1d8eb70b821ae385bc92",
         "type": "github"
       },
       "original": {
         "owner": "nixos",
-        "ref": "release-22.11",
+        "ref": "release-23.11",
         "repo": "nixpkgs",
         "type": "github"
       }
     },
     "nixpkgs-stable": {
       "locked": {
-        "lastModified": 1697655685,
-        "narHash": "sha256-79Kuv+QdgsVc+rkibuAgWHnh8IXrLBTOKg5nM0Qvux0=",
+        "lastModified": 1703992652,
+        "narHash": "sha256-C0o8AUyu8xYgJ36kOxJfXIroy9if/G6aJbNOpA5W0+M=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "80c1aab725151632ddc2a20caeb914e76dd0673c",
+        "rev": "32f63574c85fbc80e4ba1fbb932cde9619bad25e",
         "type": "github"
       },
       "original": {
         "owner": "NixOS",
-        "ref": "nixos-23.05",
+        "ref": "nixos-23.11",
         "repo": "nixpkgs",
         "type": "github"
       }
diff --git a/.github/flake.nix b/.github/flake.nix
index ed606f5..8c9b110 100644
--- a/.github/flake.nix
+++ b/.github/flake.nix
@@ -28,7 +28,7 @@
     # stable branches are recommended for CI, regression spotting.  Testing with
     # multiple versions can be done via input overrides, such as:
     # nix build .#ci --override-input nixpkgs github:nixpkgs/nixpkgs/unstable
-    nixpkgs.url = "github:nixos/nixpkgs?ref=release-22.11";
+    nixpkgs.url = "github:nixos/nixpkgs?ref=release-23.11";
     flake-utils.url = "github:numtide/flake-utils";
     emacs-overlay.url = "github:nix-community/emacs-overlay";
     # slave Emacs overlay to our nixpkgs.  This doesn't do a lot except reduce
diff --git a/lisp/erk.el b/lisp/erk.el
index 33adb99..6f9002b 100644
--- a/lisp/erk.el
+++ b/lisp/erk.el
@@ -1006,29 +1006,31 @@ With prefix argument, PREVIEW the buffer."
                        (load-theme 'modus-vivendi t) ; TODO customize
                        ;; TODO customize
                        ;; TODO use early init
-                       (setopt load-prefer-newer t
-                               inhibit-startup-message t
-                               package-enable-at-startup nil
-                               use-short-answers t
-                               use-dialog-box nil
-                               pixel-scroll-precision-mode 1
-                               ;; Recursive minibuffer too useful when introspecting
-                               enable-recursive-minibuffers t
-                               default-frame-alist
-                               '((tool-bar-lines . 0)
-                                 (menu-bar-lines . 0)
-                                 (internal-border-width . 0)
-                                 (undecorated . nil)
-                                 (background-color . "#000000") ; said to reduce startup flicker on theme
-                                 (ns-appearance . dark)         ; darwin
-                                 (ns-transparent-titlebar . t)  ; darwin
-                                 (vertical-scroll-bars . nil)
-                                 (horizontal-scroll-bars . nil)))
+                       ;; TODO switch to setopt after 28 is deprecated.
+                       (setq load-prefer-newer t
+                             inhibit-startup-message t
+                             package-enable-at-startup nil
+                             use-short-answers t
+                             use-dialog-box nil
+                             pixel-scroll-precision-mode 1
+                             ;; Recursive minibuffer too useful when introspecting
+                             enable-recursive-minibuffers t
+                             default-frame-alist
+                             '((tool-bar-lines . 0)
+                               (menu-bar-lines . 0)
+                               (internal-border-width . 0)
+                               (undecorated . nil)
+                               (background-color . "#000000") ; startup flicker
+                               (ns-appearance . dark)         ; darwin
+                               (ns-transparent-titlebar . t)  ; darwin
+                               (vertical-scroll-bars . nil)
+                               (horizontal-scroll-bars . nil)))
                        (setq load-path ',load-path)
                        (push ,package-path load-path)
                        (require ',package-feature))))
     (start-process buffer-name out-buffer emacsen
                    "-Q"
+                   "--debug-init"       ; TODO switch
                    "--init-dir" init-dir
                    "--eval" (format "%S" init-form))))