diff --git a/Makefile b/Makefile
index 012b059..3dc1399 100644
--- a/Makefile
+++ b/Makefile
@@ -30,7 +30,7 @@ source: ## Build Python source distribution package
 	poetry build --format sdist
 
 test: ## Run the project testsuite(s)
-	poetry run tox --recreate --parallelize-locked-install=10
+	poetry run tox --recreate
 
 dev: ## Create the local dev environment
 	poetry install -E poetry