diff --git a/app/pytest/pytest.ini b/app/pytest/pytest.ini
index e610b3c2..a56c8c12 100644
--- a/app/pytest/pytest.ini
+++ b/app/pytest/pytest.ini
@@ -1,3 +1,6 @@
 [pytest]
 log_cli = True
 log_cli_level = INFO
+env = 
+    JLINK_SERIAL=760208506
+    ZSWATCH_BUILD_DIR=debug_rev5
diff --git a/app/pytest/requirements.txt b/app/pytest/requirements.txt
index be1bcea3..7cd53262 100644
--- a/app/pytest/requirements.txt
+++ b/app/pytest/requirements.txt
@@ -18,8 +18,7 @@ psutil
 # Artifacts package creation
 bz
 
-# used for CAN <=> host testing
-python-can>=4.3.0
-
 # RTT connection
 pylink-square
+
+pytest-env
\ No newline at end of file
diff --git a/app/pytest/utils.py b/app/pytest/utils.py
index 5478ef85..5c9868c1 100644
--- a/app/pytest/utils.py
+++ b/app/pytest/utils.py
@@ -1,10 +1,9 @@
+import os
 import subprocess
 import logging
 import time
 import pylink
 
-SERIAL_NUMBER = "760208490"
-
 log = logging.getLogger()
 
 
@@ -22,7 +21,7 @@ def reset():
             "--family",
             "nrf53",
             "--snr",
-            SERIAL_NUMBER,
+            os.environ["JLINK_SERIAL"],
             "--reset",
         ],
         shell=False,
@@ -33,6 +32,8 @@ def reset():
 
 
 def flash():
+    log.info("Using J-Link {}".format(os.environ["JLINK_SERIAL"]))
+    
     """Flash firmware"""
     log.info("Flashing CP_APPLICATION.")
     subprocess.run(
@@ -41,7 +42,7 @@ def flash():
             "--family",
             "nrf53",
             "--snr",
-            SERIAL_NUMBER,
+            os.environ["JLINK_SERIAL"],
             "--program",
             "./zswatch_nrf5340_cpuapp@3_debug.hex",
             "--chiperase",
@@ -60,7 +61,7 @@ def flash():
             "--family",
             "nrf53",
             "--snr",
-            SERIAL_NUMBER,
+            os.environ["JLINK_SERIAL"],
             "--program",
             "./zswatch_nrf5340_CPUNET.hex",
             "--coprocessor",
@@ -81,7 +82,7 @@ def read_rtt(target_device="nRF5340_XXAA", timeout_ms=10000):
     jlink = pylink.JLink()
     logging.getLogger("pylink.jlink").setLevel(logging.WARNING)
     log.info("Connecting to JLink...")
-    jlink.open(serial_no=SERIAL_NUMBER)
+    jlink.open(serial_no=os.environ["JLINK_SERIAL"])
     log.info("Connecting to %s..." % target_device)
     jlink.set_tif(pylink.enums.JLinkInterfaces.SWD)
     jlink.connect(target_device)