diff --git a/libs/cli/langgraph_cli/config.py b/libs/cli/langgraph_cli/config.py
index be8cfd085..41832e7a0 100644
--- a/libs/cli/langgraph_cli/config.py
+++ b/libs/cli/langgraph_cli/config.py
@@ -330,7 +330,7 @@ def _assemble_local_deps(config_path: pathlib.Path, config: Config) -> LocalDeps
                 rfile = resolved / "requirements.txt"
                 pip_reqs.append(
                     (
-                        rfile.relative_to(config_path.parent),
+                        rfile.relative_to(config_path.parent).as_posix(),
                         f"{container_path}/requirements.txt",
                     )
                 )