diff --git a/js/x11/core/keysyms.update.sh b/js/x11/core/keysyms.update.sh
new file mode 100644
index 0000000..1212ee4
--- /dev/null
+++ b/js/x11/core/keysyms.update.sh
@@ -0,0 +1,35 @@
+#!/bin/bash -e
+
+keysymdef_url=http://cgit.freedesktop.org/xorg/proto/xproto/plain/keysymdef.h
+keysymdef=$(mktemp)
+
+wget $keysymdef_url -O $keysymdef
+
+(
+echo "
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *\\
+
+   This file is automatically translated from X.Org's xproto/keysymdef.h
+   Please, do not update this file with your hands, run $(basename "$0").
+
+\\* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+module.exports = {
+"
+
+sed -r '
+  s/#ifdef\s+/\/\/ Group /
+  s/#endif.*//
+  s/#define\s+([^ ]+)(\s+)([^ ]+)\s*\/\*\s*([^\*]+[^ ])\s*\*\//  \1:\2{ code: \3, description: "\4" },/
+  s/(\b)U\+([0-9A-F]+)(\b)/\1(\\u\2)\3/i
+  s/#define\s+([^ ]+)(\s+)([^ ]+)/  \1:\2{ code: \3, description: null },/
+  #s/#define\s+([^ ]+)(\s+[^ ]+)/  \1:\2,/
+' $keysymdef
+
+echo -n '
+  NoSymbol: 0
+};'
+
+) > "$(dirname "$0")/keysyms.js"
+
+rm $keysymdef