diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 64d3c166aa..d826bc8bb4 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -67,6 +67,9 @@ jobs:
         with:
           cache-prefix: ${{ runner.os }}-v${{ matrix.node-version }}
 
+      - name: verify yarn dependency duplicates
+        run: yarn dedupe --check
+
       - name: verify changesets
         run: node scripts/verify-changesets.js