diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 9a8c83bee..3be65585f 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -47,7 +47,7 @@ jobs:
 
       - name: Cache deps
         id: cache-deps
-        uses: actions/cache@v2
+        uses: actions/cache@v4
         with:
           path: .venv
           key: pydeps-${{ hashFiles('**/poetry.lock') }}
diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 000000000..955a32b10
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "openadapt-ml"]
+	path = openadapt-ml
+	url = https://github.com/OpenAdaptAI/openadapt-ml.git
diff --git a/openadapt-ml b/openadapt-ml
new file mode 160000
index 000000000..e5c051617
--- /dev/null
+++ b/openadapt-ml
@@ -0,0 +1 @@
+Subproject commit e5c0516171f79ec7504e19329e0eb355d456a721