diff --git a/.github/workflows/ensure-main-from-dev.yaml b/.github/workflows/ensure-main-from-dev.yaml
new file mode 100644
index 0000000..0c2ff23
--- /dev/null
+++ b/.github/workflows/ensure-main-from-dev.yaml
@@ -0,0 +1,21 @@
+name: Enforce PR Flow
+
+on:
+  pull_request:
+    types: [opened, synchronize, reopened, edited]
+
+jobs:
+  check-source-branch:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Check PR flow
+        run: |
+          echo "PR: ${{ github.head_ref }} -> ${{ github.base_ref }}"
+
+          if [[ "${{ github.base_ref }}" == "main" && "${{ github.head_ref }}" != "dev" ]]; then
+            echo "PRs to main must come from dev."
+            exit 1
+          fi
+
+          echo "PR flow is valid."