diff --git a/pyproject.toml b/pyproject.toml
index eff97013..07ebe3f5 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -52,6 +52,7 @@ dependencies = [
 
 [project.optional-dependencies]
 test = [
+    "jupyter-server-proxy[standalone]",
     "pytest",
     "pytest-asyncio",
     "pytest-cov",