diff --git a/nix/sources.json b/nix/sources.json
index b2a3577..812ba3c 100644
--- a/nix/sources.json
+++ b/nix/sources.json
@@ -29,10 +29,10 @@
         "homepage": "",
         "owner": "nix-community",
         "repo": "emacs-overlay",
-        "rev": "532c7403232f77e45f70fb1c4124272843e89011",
-        "sha256": "0iqhxb91n1lyvk0axy2xhyq75z8z8n0qrv1xxrb6bsn3v0ym1cmp",
+        "rev": "ef220b4a0990fd0f5dd25c588c24b2c1ad88c8fc",
+        "sha256": "0iq7zsprhiwjlcdinhqxwliiah0snvsvvsdscsfrw5h6nxidcd55",
         "type": "tarball",
-        "url": "https://github.com/nix-community/emacs-overlay/archive/532c7403232f77e45f70fb1c4124272843e89011.tar.gz",
+        "url": "https://github.com/nix-community/emacs-overlay/archive/ef220b4a0990fd0f5dd25c588c24b2c1ad88c8fc.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     },
     "emacs-so-long": {