diff --git a/pyproject.toml b/pyproject.toml
index 653d770476f..b784100f692 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -77,6 +77,7 @@ dependencies=[
     "tables<3.9;python_version == '3.8'",
     "tables; python_version >= '3.9'",
     "python-multipart",
+    "pyarrow",
 ]
 
 [project.scripts]
diff --git a/src/ert/dark_storage/app.py b/src/ert/dark_storage/app.py
index bc674c7b02c..d9b6620cb19 100644
--- a/src/ert/dark_storage/app.py
+++ b/src/ert/dark_storage/app.py
@@ -46,6 +46,7 @@ def render(self, content: Any) -> bytes:
     default_response_class=JSONResponse,
 )
 
+
 @app.on_event("startup")
 async def initialize_libres_facade() -> None:
     from ert.dark_storage.enkf import init_facade