diff --git a/controller/opt/server.py b/controller/opt/server.py
new file mode 100644
index 0000000..82a3811
--- /dev/null
+++ b/controller/opt/server.py
@@ -0,0 +1,39 @@
+import os
+import json
+
+from tornado.ioloop import IOLoop
+from tornado.web import RequestHandler, Application
+
+from tfw import FSMAwareEventHandler
+
+
+class ControllerPostHandler(RequestHandler):
+    # pylint: disable=abstract-method
+    def initialize(self, **kwargs): # pylint: disable=arguments-differ
+        self.controller = kwargs['controller']
+
+    def post(self, *args, **kwargs):
+        self.set_header('Content-Type', 'application/json')
+        self.write(json.dumps({
+            'solved': self.controller.in_accepted_state
+        }))
+
+
+class ControllerEventHandler(FSMAwareEventHandler):
+    def handle_event(self, message):
+        pass
+
+
+if __name__ == '__main__':
+    controller = ControllerEventHandler('controller')
+    application = Application([(
+        f'/{os.environ["SECRET"]}',
+        ControllerPostHandler,
+        {'controller': controller}
+    )])
+    application.listen(os.environ['CONTROLLER_PORT'])
+
+    try:
+        IOLoop.instance().start()
+    finally:
+        controller.cleanup()