diff --git a/pyproject.toml b/pyproject.toml
index 5270746..20db60b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -56,6 +56,8 @@ requires-python = ">=3.9"
 dependencies = [
     "pytrie",
     "pydantic>=2.0",
+    "eval_type_backport; python_version < '3.10'",
+    "typing-extensions",
 ]
 
 [project.optional-dependencies]