diff --git a/pyproject.toml b/pyproject.toml
index 4d2dc14..9f9c948 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -10,6 +10,7 @@ filterwarnings = [
     "error", # Fail the tests if there are any warnings.
     "ignore:^find_module\\(\\) is deprecated and slated for removal in Python 3.12; use find_spec\\(\\) instead$:DeprecationWarning:importlib",
     "ignore:^FileFinder.find_loader\\(\\) is deprecated and slated for removal in Python 3.12; use find_spec\\(\\) instead$:DeprecationWarning:importlib",
+    "ignore:^pkg_resources is deprecated as an API:DeprecationWarning:pkg_resources",
     "ignore:^pkg_resources is deprecated as an API:DeprecationWarning:pyramid",
     "ignore:^Deprecated call to .pkg_resources\\.declare_namespace\\('.*'\\).\\.:DeprecationWarning:pkg_resources",
 ]
diff --git a/tests/pytest_plugins/factory_boy.py b/tests/pytest_plugins/factory_boy.py
new file mode 100644
index 0000000..cad2ba6
--- /dev/null
+++ b/tests/pytest_plugins/factory_boy.py
@@ -0,0 +1,10 @@
+import factory.random
+import pytest
+
+
+@pytest.fixture(scope="session", autouse=True)
+def factory_boy_random_seed():
+    # Set factory_boy's random seed so that it produces the same random values
+    # in each run of the tests.
+    # See: https://factoryboy.readthedocs.io/en/latest/index.html#reproducible-random-values
+    factory.random.reseed_random("hypothesis/h-vialib")
diff --git a/tox.ini b/tox.ini
index 8f6de61..e7492c4 100644
--- a/tox.ini
+++ b/tox.ini
@@ -18,6 +18,7 @@ setenv =
     dev: SENTRY_ENVIRONMENT = {env:SENTRY_ENVIRONMENT:dev}
     dev: NEW_RELIC_APP_NAME = {env:NEW_RELIC_APP_NAME:h-vialib}
     dev: NEW_RELIC_ENVIRONMENT = {env:NEW_RELIC_ENVIRONMENT:dev}
+    tests,functests: PYTEST_PLUGINS = tests.pytest_plugins.factory_boy
 passenv =
     HOME
     PYTEST_ADDOPTS
@@ -36,6 +37,7 @@ deps =
     lint,tests,coverage: coverage[toml]
     lint,tests,functests: pytest
     lint,tests,functests: factory-boy
+    lint,tests,functests: pytest-factoryboy
     lint,tests,functests: h-matchers
     lint,template: cookiecutter
     lint,tests,functests: freezegun
@@ -52,7 +54,7 @@ commands =
     lint: pydocstyle src tests bin
     lint: pycodestyle src tests bin
     tests: coverage run -m pytest --failed-first --new-first --no-header --quiet {posargs:tests/unit/}
-    functests: pytest --failed-first --new-first --no-header --quiet {posargs:tests/functional/}
+    functests: python -m pytest --failed-first --new-first --no-header --quiet {posargs:tests/functional/}
     coverage: -coverage combine
     coverage: coverage report
     template: python3 bin/make_template {posargs}