diff --git a/core/core.el b/core/core.el
index c34e586c4..a402ff3c8 100644
--- a/core/core.el
+++ b/core/core.el
@@ -48,6 +48,12 @@
     (setq file-name-handler-alist doom--initial-file-name-handler-alist))
   (add-hook 'emacs-startup-hook #'doom-reset-file-handler-alist-h))
 
+;; REVIEW Fixes 'void-variable tab-prefix-map' errors caused by packages that
+;;        prematurely use this variable before it was introduced. Remove this in
+;;        a year.
+(unless (boundp 'tab-prefix-map)
+  (defvar tab-prefix-map (make-sparse-keymap)))
+
 ;; Just the bare necessities
 (require 'subr-x)
 (require 'cl-lib)