--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "omemo-dr"
-requires-python = ">=3.10"
+requires-python = ">=3.9"
 description = "OMEMO Double Ratchet"
 readme = "README.md"
 license = {file = "LICENSE"}
@@ -46,7 +46,7 @@ skip = "*__pycache__*,build,dist,test,*.
 ignore-words-list = "claus,pres,ser,trough"
 
 [tool.pyright]
-pythonVersion = "3.10"
+pythonVersion = "3.9"
 pythonPlatform = "All"
 typeCheckingMode = "strict"
 
--- a/tests/test_sessionbuilder.py
+++ b/tests/test_sessionbuilder.py
@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import time
 import unittest
 
--- a/tests/test_sessioncipher.py
+++ b/tests/test_sessioncipher.py
@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import unittest
 
 from omemo_dr.ecc.curve import Curve