diff --git a/pyproject.toml b/pyproject.toml
index 8969875..7dcd540 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -46,6 +46,7 @@ dependencies = [
 dev = [
     "pytest>=8.0.0",
     "pytest-asyncio>=0.23.0",
+    "respx>=0.21.0,<1.0.0",
     "pytest-mock>=3.12.0",
     "pytest-xdist>=3.5.0",
     "pytest-timeout>=2.3.0",