diff --git a/pyproject.toml b/pyproject.toml
index 628f9c0..1099932 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -55,22 +55,6 @@ classifiers = [
 [tool.black]
 line-length = 96
 
-[tool.tox]
-legacy_tox_ini = """
-[tox]
-skipsdist = True
-envlist = py37, py38, py39
-
-[testenv]
-skip_install = true
-whitelist_externals = poetry
-commands =
-    poetry install -vvv
-    poetry run mypy --strict --no-strict-equality pvss tests
-    poetry run coverage erase
-    poetry run coverage run -m pytest -v --strict tests
-    poetry run coverage html
-"""
 
 [tool.coverage]
     [tool.coverage.report]
diff --git a/tox.ini b/tox.ini
new file mode 100644
index 0000000..cf8c737
--- /dev/null
+++ b/tox.ini
@@ -0,0 +1,16 @@
+[tox]
+isolated_build = true
+skipsdist = true
+envlist = py39, py310, py311
+
+[testenv]
+skip_install = true
+allowlist_externals = poetry
+commands_pre =
+    poetry install
+commands =
+    poetry run mypy --strict --no-strict-equality pvss tests
+    poetry run coverage erase
+    poetry run coverage run -m pytest -v --strict-markers tests
+    poetry run coverage html
+    poetry run isort -c --diff pvss tests