diff --git a/src/net/tools/naive/naive_proxy_bin.cc b/src/net/tools/naive/naive_proxy_bin.cc
index 3177de6e..1a5406c1 100644
--- a/src/net/tools/naive/naive_proxy_bin.cc
+++ b/src/net/tools/naive/naive_proxy_bin.cc
@@ -533,6 +533,9 @@ int main(int argc, char* argv[]) {
     naive_proxies.push_back(std::move(naive_proxy));
   }
 
+  if (getenv("TEST_MARK_STARTUP") != nullptr) {
+    LOG(INFO) << "TEST_MARK_STARTUP";
+  }
   base::RunLoop().Run();
 
   return EXIT_SUCCESS;
diff --git a/tests/basic.py b/tests/basic.py
index a684a649..010cb5ea 100644
--- a/tests/basic.py
+++ b/tests/basic.py
@@ -97,7 +97,9 @@ def start_naive(naive_args, config_file):
         cmdline = [argv.naive]
     cmdline.extend(naive_args)
 
-    proc = subprocess.Popen(cmdline, stdout=subprocess.DEVNULL,
+    env = os.environ.copy()
+    env["TEST_MARK_STARTUP"] = "yes"
+    proc = subprocess.Popen(cmdline, stdout=subprocess.DEVNULL, env=env,
                             stderr=subprocess.PIPE, text=True, encoding='utf-8')
     print('subprocess.Popen', ' '.join(cmdline), 'pid:', proc.pid)
 
@@ -122,7 +124,7 @@ def start_naive(naive_args, config_file):
             print('terminate pid', proc.pid)
             proc.terminate()
             return 'Failed to listen'
-        elif 'Listening on ' in line:
+        elif 'TEST_MARK_STARTUP' in line:
             timeout.cancel()
             return proc