diff --git a/pkgs/development/python-modules/cross-web/default.nix b/pkgs/development/python-modules/cross-web/default.nix
index 8d69ff5d6211..86e7981a9d8e 100644
--- a/pkgs/development/python-modules/cross-web/default.nix
+++ b/pkgs/development/python-modules/cross-web/default.nix
@@ -70,6 +70,11 @@ buildPythonPackage (finalAttrs: {
   ]
   ++ lib.concatAttrValues finalAttrs.passthru.optional-dependencies;
 
+  pytestFlags = [
+    # Using `httpx` with `starlette.testclient` is deprecated; install `httpx2` instead.
+    "-Wignore::starlette.exceptions.StarletteDeprecationWarning"
+  ];
+
   pythonImportsCheck = [ "cross_web" ];
 
   preCheck = ''