diff --git a/tools/Makefile b/tools/Makefile
index 37a6d93e7..578884c69 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -2,10 +2,10 @@ all: lint test
 
 include python.mk
 
-PIP_INSTALL := -r requirements-dev.txt
-PYLINT_ARG := tools
-MYPY_ARG := .
-PYTEST_ARG := .
+PIP_INSTALL = -r requirements-dev.txt
+PYLINT_ARG = tools
+MYPY_ARG = .
+PYTEST_ARG = .
 
 format: .format
 lint: .pylint .mypy
diff --git a/tools/python.mk b/tools/python.mk
index b80f0d61f..d5117d1fa 100644
--- a/tools/python.mk
+++ b/tools/python.mk
@@ -1,14 +1,14 @@
 .ONESHELL:
 
-SHELL := bash
-CPU_CORES := $(shell nproc)
+SHELL = bash
+CPU_CORES = $(shell nproc)
 
-# PIP_INSTALL := --editable .[dev]
-# PYLINT_ARG :=
-# MYPY_ARG :=
-# PYTEST_ARG :=
+# PIP_INSTALL = --editable .
+# PYLINT_ARG =
+# MYPY_ARG =
+# PYTEST_ARG =
 
-VENV := venv
+VENV = venv
 $(VENV):
 	python3 -m venv $(VENV)
 	source $(VENV)/bin/activate