diff --git a/support/testing/tests/package/test_python_autobahn.py b/support/testing/tests/package/test_python_autobahn.py
index a237ce465d..6c1678a615 100644
--- a/support/testing/tests/package/test_python_autobahn.py
+++ b/support/testing/tests/package/test_python_autobahn.py
@@ -3,9 +3,17 @@ from tests.package.test_python import TestPythonPackageBase
 
 class TestPythonPy3Autobahn(TestPythonPackageBase):
     __test__ = True
-    config = TestPythonPackageBase.config + \
+    # Need to use a different toolchain than the default due to
+    # python-cryptography using Rust (not available with uclibc)
+    config = \
         """
+        BR2_arm=y
+        BR2_TOOLCHAIN_EXTERNAL=y
+        BR2_TOOLCHAIN_EXTERNAL_BOOTLIN=y
+        BR2_TOOLCHAIN_EXTERNAL_BOOTLIN_ARMV5_EABI_GLIBC_STABLE=y
         BR2_PACKAGE_PYTHON3=y
         BR2_PACKAGE_PYTHON_AUTOBAHN=y
+        BR2_TARGET_ROOTFS_CPIO=y
+        # BR2_TARGET_ROOTFS_TAR is not set
         """
     sample_scripts = ["tests/package/sample_python_autobahn.py"]
diff --git a/support/testing/tests/package/test_python_crossbar.py b/support/testing/tests/package/test_python_crossbar.py
index d7843ddd8b..83649aeec2 100644
--- a/support/testing/tests/package/test_python_crossbar.py
+++ b/support/testing/tests/package/test_python_crossbar.py
@@ -3,10 +3,18 @@ from tests.package.test_python import TestPythonPackageBase
 
 class TestPythonPy3Crossbar(TestPythonPackageBase):
     __test__ = True
-    config = TestPythonPackageBase.config + \
+    # Need to use a different toolchain than the default due to
+    # python-cryptography using Rust (not available with uclibc)
+    config = \
         """
+        BR2_arm=y
+        BR2_TOOLCHAIN_EXTERNAL=y
+        BR2_TOOLCHAIN_EXTERNAL_BOOTLIN=y
+        BR2_TOOLCHAIN_EXTERNAL_BOOTLIN_ARMV5_EABI_GLIBC_STABLE=y
         BR2_PACKAGE_PYTHON3=y
         BR2_PACKAGE_PYTHON_CROSSBAR=y
+        BR2_TARGET_ROOTFS_CPIO=y
+        # BR2_TARGET_ROOTFS_TAR is not set
         """
     sample_scripts = ["tests/package/sample_python_crossbar.py"]
     timeout = 60
diff --git a/support/testing/tests/package/test_python_cryptography.py b/support/testing/tests/package/test_python_cryptography.py
index 62f0ca0def..bf11c02e5c 100644
--- a/support/testing/tests/package/test_python_cryptography.py
+++ b/support/testing/tests/package/test_python_cryptography.py
@@ -3,10 +3,18 @@ from tests.package.test_python import TestPythonPackageBase
 
 class TestPythonPy3Cryptography(TestPythonPackageBase):
     __test__ = True
-    config = TestPythonPackageBase.config + \
+    # Need to use a different toolchain than the default due to
+    # python-cryptography using Rust (not available with uclibc)
+    config = \
         """
+        BR2_arm=y
+        BR2_TOOLCHAIN_EXTERNAL=y
+        BR2_TOOLCHAIN_EXTERNAL_BOOTLIN=y
+        BR2_TOOLCHAIN_EXTERNAL_BOOTLIN_ARMV5_EABI_GLIBC_STABLE=y
         BR2_PACKAGE_PYTHON3=y
         BR2_PACKAGE_PYTHON_CRYPTOGRAPHY=y
+        BR2_TARGET_ROOTFS_CPIO=y
+        # BR2_TARGET_ROOTFS_TAR is not set
         """
     sample_scripts = ["tests/package/sample_python_cryptography.py"]
     timeout = 40
diff --git a/support/testing/tests/package/test_python_service_identity.py b/support/testing/tests/package/test_python_service_identity.py
index 09cfbe0a26..dbad5f931f 100644
--- a/support/testing/tests/package/test_python_service_identity.py
+++ b/support/testing/tests/package/test_python_service_identity.py
@@ -3,10 +3,18 @@ from tests.package.test_python import TestPythonPackageBase
 
 class TestPythonPy3ServiceIdentity(TestPythonPackageBase):
     __test__ = True
-    config = TestPythonPackageBase.config + \
+    # Need to use a different toolchain than the default due to
+    # python-cryptography using Rust (not available with uclibc)
+    config = \
         """
+        BR2_arm=y
+        BR2_TOOLCHAIN_EXTERNAL=y
+        BR2_TOOLCHAIN_EXTERNAL_BOOTLIN=y
+        BR2_TOOLCHAIN_EXTERNAL_BOOTLIN_ARMV5_EABI_GLIBC_STABLE=y
         BR2_PACKAGE_PYTHON3=y
         BR2_PACKAGE_PYTHON_SERVICE_IDENTITY=y
+        BR2_TARGET_ROOTFS_CPIO=y
+        # BR2_TARGET_ROOTFS_TAR is not set
         """
     sample_scripts = ["tests/package/sample_python_service_identity.py"]
     timeout = 30
diff --git a/support/testing/tests/package/test_python_treq.py b/support/testing/tests/package/test_python_treq.py
index 307c9932b2..515f1ea304 100644
--- a/support/testing/tests/package/test_python_treq.py
+++ b/support/testing/tests/package/test_python_treq.py
@@ -14,8 +14,16 @@ class TestPythonTreq(TestPythonPackageBase):
 
 class TestPythonPy3Treq(TestPythonTreq):
     __test__ = True
-    config = TestPythonTreq.config + \
+    # Need to use a different toolchain than the default due to
+    # python-cryptography using Rust (not available with uclibc)
+    config = \
         """
+        BR2_arm=y
+        BR2_TOOLCHAIN_EXTERNAL=y
+        BR2_TOOLCHAIN_EXTERNAL_BOOTLIN=y
+        BR2_TOOLCHAIN_EXTERNAL_BOOTLIN_ARMV5_EABI_GLIBC_STABLE=y
         BR2_PACKAGE_PYTHON3=y
         BR2_PACKAGE_PYTHON_TREQ=y
+        BR2_TARGET_ROOTFS_CPIO=y
+        # BR2_TARGET_ROOTFS_TAR is not set
         """
diff --git a/support/testing/tests/package/test_python_txtorcon.py b/support/testing/tests/package/test_python_txtorcon.py
index 8e74190ee1..6f0c4ca1ed 100644
--- a/support/testing/tests/package/test_python_txtorcon.py
+++ b/support/testing/tests/package/test_python_txtorcon.py
@@ -3,10 +3,18 @@ from tests.package.test_python import TestPythonPackageBase
 
 class TestPythonPy3Txtorcon(TestPythonPackageBase):
     __test__ = True
-    config = TestPythonPackageBase.config + \
+    # Need to use a different toolchain than the default due to
+    # python-cryptography using Rust (not available with uclibc)
+    config = \
         """
+        BR2_arm=y
+        BR2_TOOLCHAIN_EXTERNAL=y
+        BR2_TOOLCHAIN_EXTERNAL_BOOTLIN=y
+        BR2_TOOLCHAIN_EXTERNAL_BOOTLIN_ARMV5_EABI_GLIBC_STABLE=y
         BR2_PACKAGE_PYTHON3=y
         BR2_PACKAGE_PYTHON_TXTORCON=y
+        BR2_TARGET_ROOTFS_CPIO=y
+        # BR2_TARGET_ROOTFS_TAR is not set
         """
     sample_scripts = ["tests/package/sample_python_txtorcon.py"]
     timeout = 30