diff --git a/examples/protocols/mdns/mdns_example_test.py b/examples/protocols/mdns/mdns_example_test.py
index e86b84e42..af897bb79 100644
--- a/examples/protocols/mdns/mdns_example_test.py
+++ b/examples/protocols/mdns/mdns_example_test.py
@@ -1,6 +1,5 @@
 import re
 import os
-import sys
 import socket
 import time
 import struct
@@ -8,22 +7,8 @@ import dpkt
 import dpkt.dns
 from threading import Thread, Event
 
-
-# this is a test case write with tiny-test-fw.
-# to run test cases outside tiny-test-fw,
-# we need to set environment variable `TEST_FW_PATH`,
-# then get and insert `TEST_FW_PATH` to sys path before import FW module
-
-try:
-    import IDF
-    from IDF.IDFDUT import ESP32DUT
-except ImportError:
-    test_fw_path = os.getenv("TEST_FW_PATH")
-    if test_fw_path and test_fw_path not in sys.path:
-        sys.path.insert(0, test_fw_path)
-    import IDF
-
-import DUT
+from tiny_test_fw import DUT
+import ttfw_idf
 
 # g_run_server = True
 # g_done = False
@@ -103,7 +88,7 @@ def mdns_server(esp_host):
             continue
 
 
-@IDF.idf_example_test(env_tag="Example_WIFI")
+@ttfw_idf.idf_example_test(env_tag="Example_WIFI")
 def test_examples_protocol_mdns(env, extra_data):
     global stop_mdns_server
     """
@@ -113,12 +98,12 @@ def test_examples_protocol_mdns(env, extra_data):
       3. check the mdns name is accessible
       4. check DUT output if mdns advertized host is resolved
     """
-    dut1 = env.get_dut("mdns-test", "examples/protocols/mdns", dut_class=ESP32DUT)
+    dut1 = env.get_dut("mdns-test", "examples/protocols/mdns", dut_class=ttfw_idf.ESP32DUT)
     # check and log bin size
     binary_file = os.path.join(dut1.app.binary_path, "mdns-test.bin")
     bin_size = os.path.getsize(binary_file)
-    IDF.log_performance("mdns-test_bin_size", "{}KB".format(bin_size // 1024))
-    IDF.check_performance("mdns-test_bin_size", bin_size // 1024)
+    ttfw_idf.log_performance("mdns-test_bin_size", "{}KB".format(bin_size // 1024))
+    ttfw_idf.check_performance("mdns-test_bin_size", bin_size // 1024)
     # 1. start mdns application
     dut1.start_app()
     # 2. get the dut host name (and IP address)