diff --git a/piker/service/_actor_runtime.py b/piker/service/_actor_runtime.py
index 33f23453..14751304 100644
--- a/piker/service/_actor_runtime.py
+++ b/piker/service/_actor_runtime.py
@@ -124,6 +124,10 @@ async def open_piker_runtime(
                 enable_modules=enable_modules,
                 hide_tb=False,
 
+                # TODO: how to configure this?
+                # keep it on by default if debug mode is set?
+                maybe_enable_greenback=False,
+
                 **tractor_kwargs,
             ) as actor,