diff --git a/pyproject.toml b/pyproject.toml
index 60e7cfd..9c0936f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -22,7 +22,7 @@ classifiers = [
 ]
 
 [tool.poetry.dependencies]
-python = "^3.8"
+python = "=3.9"
 numpy = "1.23.3"
 chacha20poly1305 = "0.0.3"
 cryptography = "38.0.1"