diff --git a/modules/languages/siren-json.el b/modules/languages/siren-json.el
index 923ae81..1bc3fc8 100644
--- a/modules/languages/siren-json.el
+++ b/modules/languages/siren-json.el
@@ -11,7 +11,7 @@
 
 (use-package json-mode
   :mode "\\.json\\'"
-  :requires (flycheck highlight-indentation omnifmt hideshowvis)
+  :requires (flycheck highlight-indentation hideshowvis)
 
   :bind (:map json-mode-map
               ("C-j" . newline-and-indent)
diff --git a/vendor/omnifmt.el b/vendor/omnifmt.el
deleted file mode 100644
index b5c326e..0000000
--- a/vendor/omnifmt.el
+++ /dev/null
@@ -1,58 +0,0 @@
-;;; omnifmt.el --- Run omnifmt on buffers when saving them
-
-;; Copyright (C) 2016 Lorenzo Villani
-;;
-;; Author: Lorenzo Villani <lorenzo@villani.me>
-;; Maintainer: Lorenzo Villani <lorenzo@villani.me>
-;; Created: 27 Dec 2015
-;;
-;; Keywords: languages, tools
-;; Homepage: https://github.com/omnitools/omnifmt-emacs
-
-;; This file is not part of GNU Emacs.
-
-;; This program is free software: you can redistribute it and/or modify
-;; it under the terms of the GNU General Public License as published by
-;; the Free Software Foundation, version 3 of the License.
-;;
-;; This program is distributed in the hope that it will be useful,
-;; but WITHOUT ANY WARRANTY; without even the implied warranty of
-;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-;; GNU General Public License for more details.
-;;
-;; You should have received a copy of the GNU General Public License
-;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-;;; Code:
-
-;;;###autoload
-(define-minor-mode omnifmt-mode
-  "Enable format-on-save for all supported files through omnifmt"
-  :lighter " fmt"
-  (if omnifmt-mode
-      (add-hook 'before-save-hook 'omnifmt-before-save t t)
-    (remove-hook 'before-save-hook 'omnifmt-before-save t)))
-
-;;;###autoload
-(define-globalized-minor-mode global-omnifmt-mode omnifmt-mode (lambda () (omnifmt-mode t)))
-
-(defun omnifmt-before-save ()
-  (let ((command `("omnifmt" "--editor" "emacs" "--editor-syntax" ,(symbol-name major-mode) "-"))
-        (old-point (point))
-        (old-window-start (window-start))
-        (tmp-buffer (get-buffer-create " *omnifmt*")))
-    (unless (null command)
-      (message "Formatting buffer...")
-      (unwind-protect
-        (when (zerop (omnifmt-run-command tmp-buffer command))
-          (erase-buffer)
-          (insert-buffer-substring tmp-buffer)
-          (goto-char old-point)
-          (set-window-start (get-buffer-window) old-window-start t))
-        (kill-buffer tmp-buffer)))))
-
-(defun omnifmt-run-command (buf command)
-  (apply #'call-process-region (point-min) (point-max) (car command) nil buf nil (cdr command)))
-
-(provide 'omnifmt)
-;;; omnifmt.el ends here