diff --git a/.isort.cfg b/.isort.cfg
index 925b940cd..109f5c21e 100644
--- a/.isort.cfg
+++ b/.isort.cfg
@@ -1,4 +1,5 @@
 [settings]
+py_version=39
 known_first_party=anki,aqt,tests
 profile=black
 extend_skip=qt/bundle
diff --git a/.ruff.toml b/.ruff.toml
new file mode 100644
index 000000000..498ecbdac
--- /dev/null
+++ b/.ruff.toml
@@ -0,0 +1,2 @@
+target-version = "py39"
+extend-exclude = ["qt/bundle"]
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 000000000..56f5c4aeb
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,3 @@
+[tool.black]
+target-version = ["py39", "py310", "py311", "py312"]
+extend-exclude = "qt/bundle"
diff --git a/qt/.isort.cfg b/qt/.isort.cfg
index 6559fce4f..aa01f87c7 100644
--- a/qt/.isort.cfg
+++ b/qt/.isort.cfg
@@ -1,4 +1,5 @@
 [settings]
+py_version=39
 profile=black
 known_first_party=anki,aqt
 extend_skip=aqt/forms,hooks_gen.py