diff --git a/tools/build/build.py b/tools/build/build.py
index 2b19977b..a86042a7 100755
--- a/tools/build/build.py
+++ b/tools/build/build.py
@@ -90,7 +90,8 @@ def build_oxjs(downloads=False, geo=False):
     # FIXME: Document what exactly the following dependecies are!
     filenames = [
         ['Fallback.js', 'Core.js'],
-        ['Collection.js', 'Math.js']
+        # Constants.js needs Ox.toArray to determine Ox.PATH
+        ['Array.js', 'Math.js']
     ]
     js = ''
     js_dir = 'Ox/js/'