diff --git a/lib/tfw/components/pipe_io_event_handler.py b/lib/tfw/components/pipe_io_event_handler.py
index c0f54aa..d0eda41 100644
--- a/lib/tfw/components/pipe_io_event_handler.py
+++ b/lib/tfw/components/pipe_io_event_handler.py
@@ -129,7 +129,7 @@ class CommandEventHandler(PipeIOEventHandler):
         return_code = self._proc.wait()
         if return_code != 0:
             _, stderr = self._proc.communicate()
-            raise RuntimeError(f'Subprocess failed: {stderr.decode()}')
+            raise RuntimeError(f'Subprocess failed ({return_code})! Stderr:\n{stderr.decode()}')
 
     def cleanup(self):
         with suppress(ProcessLookupError):