diff --git a/lib/tfw/builtins/__init__.py b/lib/tfw/builtins/__init__.py
index 9061f3d..129296d 100644
--- a/lib/tfw/builtins/__init__.py
+++ b/lib/tfw/builtins/__init__.py
@@ -3,7 +3,7 @@ from .frontend_event_handler import FrontendEventHandler
 from .fsm_managing_event_handler import FSMManagingEventHandler
 from .ide_event_handler import IdeEventHandler
 from .log_monitoring_event_handler import LogMonitoringEventHandler
-from .pipe_io_event_handler import PipeIOEventHandlerBase, PipeIOEventHandler, PipeIOServer
+from .pipe_io_event_handler import PipeIOEventHandlerBase, PipeIOEventHandler
 from .pipe_io_event_handler import TransformerPipeIOEventHandler, CommandEventHandler
 from .process_managing_event_handler import ProcessManagingEventHandler
 from .terminal_event_handler import TerminalEventHandler