diff --git a/setup/extensions.py b/setup/extensions.py
index f43dc1eef0..37cb0899f5 100644
--- a/setup/extensions.py
+++ b/setup/extensions.py
@@ -300,7 +300,7 @@ class Build(Command):
         self.obj_dir = os.path.join(os.path.dirname(SRC), 'build', 'objects')
         if not os.path.exists(self.obj_dir):
             os.makedirs(self.obj_dir)
-        if not opts.only:
+        if opts.only in {'all', 'style'}:
             self.build_style(self.j(self.SRC, 'calibre', 'plugins'))
         for ext in extensions:
             if opts.only != 'all' and opts.only != ext.name: