diff --git a/pyproject.toml b/pyproject.toml
index 67122b9..067172e 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -15,6 +15,7 @@ dependencies = [
     "typing_extensions",
 ]
 dynamic = ["version"]
+requires-python = ">= 3.11"
 
 [project.optional-dependencies]
 all = ["kupferbootstrap[dev]", "kupferbootstrap[docs]"]