diff --git a/python/pyproject.toml b/python/pyproject.toml
index 94f1f78..0dc4c9c 100644
--- a/python/pyproject.toml
+++ b/python/pyproject.toml
@@ -21,6 +21,13 @@ dynamic = ["version"]
 description = "N-dimensional, multiresolution file format for Micro-Manager"
 readme = "README.md"
 
+
+[project.optional-dependencies]
+test = [
+    "pytest",
+]
+
+
 [tool.pytest.ini_options]
 testpaths = [
     "python/ndstorage/test",