diff --git a/tools/build/build.py b/tools/build/build.py
index 0c9fb599..51851a04 100755
--- a/tools/build/build.py
+++ b/tools/build/build.py
@@ -29,6 +29,17 @@ def build_oxjs(downloads=False, geo=False):
     year = time.strftime('%Y', time.gmtime())
     comment = ' OxJS %s (c) %s 0x2620, dual-licensed GPL/MIT, see https://oxjs.org for details ' % (version, year)
 
+    # Empty build and dev
+    for path in [build_path, dev_path]:
+        if os.path.exists(path):
+            for item in os.listdir(path):
+                full_path = '%s%s' % (path, item)
+                if os.path.isdir(full_path):
+                    if not (geo == False and item == 'Ox.Geo'):
+                        shutil.rmtree(full_path)
+                else:
+                    os.remove(full_path)
+
     # Ox.UI Theme Data
     theme_data = {}
     themes = [dirname for dirname in os.listdir(source_path + 'Ox.UI/themes/') if not dirname[0] in '._']