diff --git a/.github/workflows/staging-deploy-pr.yml b/.github/workflows/staging-deploy-pr.yml
index 17de3f48ba..ada1b8b9a1 100644
--- a/.github/workflows/staging-deploy-pr.yml
+++ b/.github/workflows/staging-deploy-pr.yml
@@ -162,7 +162,7 @@ jobs:
         run: npm ci
 
       - name: Install one-off development-only dependencies
-        run: npm install --no-save esm
+        run: npm install --no-save --include=optional esm
 
       - name: Deploy
         id: deploy
diff --git a/.github/workflows/staging-undeploy-pr.yml b/.github/workflows/staging-undeploy-pr.yml
index cfcb11b396..ab41d61b9a 100644
--- a/.github/workflows/staging-undeploy-pr.yml
+++ b/.github/workflows/staging-undeploy-pr.yml
@@ -36,7 +36,7 @@ jobs:
         run: npm ci
 
       - name: Install one-off development-only dependencies
-        run: npm install --no-save esm
+        run: npm install --no-save --include=optional esm
 
       - name: Undeploy
         uses: actions/github-script@2b34a689ec86a68d8ab9478298f91d5401337b7d