diff --git a/.github/workflows/lint-and-unit-tests.yml b/.github/workflows/lint-and-unit-tests.yml
index c90cbab..0cc5d78 100644
--- a/.github/workflows/lint-and-unit-tests.yml
+++ b/.github/workflows/lint-and-unit-tests.yml
@@ -17,10 +17,9 @@ jobs:
       fail-fast: false
       matrix:
         python-version:
-          - "3.8"
-          - "3.9"
           - "3.10"
           - "3.11"
+          - "3.12"
     steps:
       - name: Checkout repo
         uses: actions/checkout@v4
diff --git a/Makefile b/Makefile
index d760ea1..552a501 100644
--- a/Makefile
+++ b/Makefile
@@ -18,6 +18,7 @@ VIRTUALENV_DIR ?= virtualenv
 
 ST2_REPO_PATH ?= /tmp/st2
 ST2_REPO_BRANCH ?= master
+PYBIN := python3
 
 PIP_OPTIONS := $(ST2_PIP_OPTIONS)
 
@@ -44,27 +45,43 @@ play:
 	@echo "`cat /etc/os-release`"
 	@echo
 
+.PHONY: clean
+clean:
+	@echo
+	@echo "==================== clean cache files and virtualenv ===================="
+	@echo
+	rm -rf ./.pytest_cache ./virtualenv ./st2_auth_ldap.egg-info
+	find . -iname '*.pyc' -delete
+	find . -iname '__pycache__' -delete
+
 .PHONY: requirements
 requirements: .clone_st2_repo virtualenv
 	@echo
 	@echo "==================== requirements ===================="
 	@echo
-	$(eval PIP_VERSION := $(shell grep 'PIP_VERSION ?= ' /tmp/st2/Makefile | awk '{ print $$3}'))
-	$(VIRTUALENV_DIR)/bin/pip install --upgrade "pip==$(PIP_VERSION)"
-	$(VIRTUALENV_DIR)/bin/pip install --cache-dir $(HOME)/.pip-cache $(PIP_OPTIONS) -r $(ST2_REPO_PATH)/requirements.txt
-	$(VIRTUALENV_DIR)/bin/pip install --cache-dir $(HOME)/.pip-cache $(PIP_OPTIONS) -r $(ST2_REPO_PATH)/test-requirements.txt
-	$(VIRTUALENV_DIR)/bin/pip install --cache-dir $(HOME)/.pip-cache $(PIP_OPTIONS) -r requirements.txt
-	$(VIRTUALENV_DIR)/bin/pip install --cache-dir $(HOME)/.pip-cache $(PIP_OPTIONS) -r test-requirements.txt
+	$(eval PIP_VERSION ?= $(shell awk '/^PIP_VERSION/ {print $$3}' /tmp/st2/Makefile))
+	$(eval SETUPTOOLS_VERSION ?= $(shell awk '/^SETUPTOOLS_VERSION/ {print $$3}' /tmp/st2/Makefile))
+	@echo
+	@echo
+	@echo Install pip $(PIP_VERSION) and setuptools $(SETUPTOOLS_VERSION) to match st2 core.
+	@echo
+	@echo
+	$(VIRTUALENV_DIR)/bin/$(PYBIN) -m pip install --upgrade "pip==$(PIP_VERSION)"
+	$(VIRTUALENV_DIR)/bin/$(PYBIN) -m pip install --upgrade "setuptools==$(SETUPTOOLS_VERSION)"
+	$(VIRTUALENV_DIR)/bin/$(PYBIN) -m pip install --cache-dir $(HOME)/.pip-cache $(PIP_OPTIONS) -r $(ST2_REPO_PATH)/requirements.txt
+	$(VIRTUALENV_DIR)/bin/$(PYBIN) -m pip install --cache-dir $(HOME)/.pip-cache $(PIP_OPTIONS) -r $(ST2_REPO_PATH)/test-requirements.txt
+	$(VIRTUALENV_DIR)/bin/$(PYBIN) -m pip install --cache-dir $(HOME)/.pip-cache $(PIP_OPTIONS) -r requirements.txt
+	$(VIRTUALENV_DIR)/bin/$(PYBIN) -m pip install --cache-dir $(HOME)/.pip-cache $(PIP_OPTIONS) -r test-requirements.txt
 
 	@echo ""
 	@echo "================== register st2auth ======================"
 	@echo ""
 	# Install st2auth
-	(. $(VIRTUALENV_DIR)/bin/activate; cd $(ST2_REPO_PATH)/st2auth; python3 setup.py develop --no-deps)
+	(. $(VIRTUALENV_DIR)/bin/activate; cd $(ST2_REPO_PATH)/st2auth; $(PYBIN) -m pip install --no-deps --editable .)
 	@echo ""
 	@echo "================== register ldap ======================"
 	@echo ""
-	(. $(VIRTUALENV_DIR)/bin/activate; python3 setup.py develop --no-deps)
+	(. $(VIRTUALENV_DIR)/bin/activate; $(PYBIN) -m pip install --no-deps --editable .)
 
 .PHONY: requirements-ci
 
@@ -74,7 +91,7 @@ $(VIRTUALENV_DIR)/bin/activate:
 	@echo
 	@echo "==================== virtualenv ===================="
 	@echo
-	test -d $(VIRTUALENV_DIR) || virtualenv $(VIRTUALENV_DIR) -p python3
+	test -d $(VIRTUALENV_DIR) || $(PYBIN) -m venv $(VIRTUALENV_DIR)
 
 	# Setup PYTHONPATH in bash activate script...
 	# Delete existing entries (if any)
@@ -126,7 +143,7 @@ unit-tests: requirements .clone_st2_repo .unit-tests
 .PHONY: .clone_st2_repo
 .clone_st2_repo:
 	@echo
-	@echo "==================== cloning st2 repo ===================="
+	@echo "==================== cloning st2 repo [$(ST2_REPO_BRANCH)] ===================="
 	@echo
 	@rm -rf /tmp/st2
 	@git clone https://github.com/StackStorm/st2.git --depth 1 --single-branch --branch $(ST2_REPO_BRANCH) /tmp/st2
diff --git a/requirements.txt b/requirements.txt
index e8d2b26..0cc2efd 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,4 +4,4 @@ python-ldap>=3.4.0,<3.5.0
 #   - 3.1 adds python3.8
 #   - 4.2 adds python3.9
 #   - 5.2.1 adds python3.11
-cachetools>=3.1,<5.4.0
+cachetools<5.4.0,>=3.1
diff --git a/tests/unit/test_config.py b/tests/unit/test_config.py
index 597d088..4a34def 100644
--- a/tests/unit/test_config.py
+++ b/tests/unit/test_config.py
@@ -275,7 +275,7 @@ def test_client_options(self):
     def test_invalid_group_dns_check_option(self):
         expected_msg = ('Invalid value "invalid" for group_dns_check option. Valid '
                         'values are: and, or.')
-        self.assertRaisesRegexp(
+        self.assertRaisesRegex(
             ValueError,
             expected_msg,
             ldap_backend.LDAPAuthenticationBackend,
diff --git a/tox.ini b/tox.ini
index 3731163..e47aca1 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist = py38,py39,py310,py311,lint
+envlist = py310,py311,py312,lint
 
 [testenv]
 deps = -r{toxinidir}/requirements.txt