diff --git a/pyproject.toml b/pyproject.toml
index d77d6f0..056f796 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -29,7 +29,7 @@ dependencies = [
     "requests>=2.33.1,<3.0.0",
     "openfeature-sdk==0.4.2", 
     "typing_extensions>=4.9.0,<5.0.0",
-    "httpx==0.27.2",
+    "httpx>=0.27.2,<1.0.0",
     "protobuf>=5.29.5,<7.0.0"
 ]
 requires-python = ">=3.10"