diff --git a/bin/tests/system/conftest.py b/bin/tests/system/conftest.py
index 96de101c3c..009d989ceb 100644
--- a/bin/tests/system/conftest.py
+++ b/bin/tests/system/conftest.py
@@ -1,5 +1,3 @@
-#!/usr/bin/python3
-
 # Copyright (C) Internet Systems Consortium, Inc. ("ISC")
 #
 # SPDX-License-Identifier: MPL-2.0
@@ -12,25 +10,43 @@
 # information regarding copyright ownership.
 
 import os
-
 import pytest
 
 
-@pytest.fixture(scope="session")
+# ======================= LEGACY=COMPATIBLE FIXTURES =========================
+# The following fixtures are designed to work with both pytest system test
+# runner and the legacy system test framework.
+
+
+@pytest.fixture(scope="module")
 def named_port():
     return int(os.environ.get("PORT", default=5300))
 
 
-@pytest.fixture(scope="session")
+@pytest.fixture(scope="module")
 def named_tlsport():
     return int(os.environ.get("TLSPORT", default=8853))
 
 
-@pytest.fixture(scope="session")
+@pytest.fixture(scope="module")
 def named_httpsport():
     return int(os.environ.get("HTTPSPORT", default=4443))
 
 
-@pytest.fixture(scope="session")
+@pytest.fixture(scope="module")
 def control_port():
     return int(os.environ.get("CONTROLPORT", default=9953))
+
+
+# ======================= PYTEST SYSTEM TEST RUNNER ==========================
+# From this point onward, any setting, fixtures or functions only apply to the
+# new pytest runner. Ideally, these would be in a separate file. However, due
+# to how pytest works and how it's used by the legacy runner, the best approach
+# is to have everything in this file to avoid duplication and set the
+# LEGACY_TEST_RUNNER if pytest is executed from the legacy framework.
+#
+# FUTURE: Once legacy runner is no longer supported, remove the env var and
+# don't branch the code.
+
+if os.getenv("LEGACY_TEST_RUNNER", "0") == "0":
+    pass  # will be implemented in followup commits
diff --git a/bin/tests/system/run.sh.in b/bin/tests/system/run.sh.in
index 81038f1eb1..a0abb1d8dd 100644
--- a/bin/tests/system/run.sh.in
+++ b/bin/tests/system/run.sh.in
@@ -230,7 +230,7 @@ if [ $status -eq 0 ]; then
             if start_servers; then
                 run=$((run+1))
                 test_status=0
-                (cd "$systest" && "$PYTEST" -rsxX -v "$test" "$@" || echo "$?" > "$test.status") | SYSTESTDIR="$systest" cat_d
+                (cd "$systest" && LEGACY_TEST_RUNNER=1 "$PYTEST" -rsxX -v "$test" "$@" || echo "$?" > "$test.status") | SYSTESTDIR="$systest" cat_d
                 if [ -f "$systest/$test.status" ]; then
                     if [ "$(cat "$systest/$test.status")" = "5" ]; then
                         echowarn "R:$systest:SKIPPED"