diff --git a/.github/workflows/manual-rebuild-dev.yml b/.github/workflows/manual-rebuild-dev.yml
index fcf6d00f..e998eef2 100644
--- a/.github/workflows/manual-rebuild-dev.yml
+++ b/.github/workflows/manual-rebuild-dev.yml
@@ -36,6 +36,12 @@ jobs:
         with:
           node-version: ${{ matrix.node-version }}
 
+      # sharp@0.23.4 falls back to node-gyp; old gyp needs Python <3.11 ('rU' mode).
+      - name: Use Python 3.10 for node-gyp
+        uses: actions/setup-python@v4
+        with:
+          python-version: '3.10'
+
       - name: Build server app using Nodejs
         run: |
           docker ps
diff --git a/.github/workflows/manual-rebuild-prod.yml b/.github/workflows/manual-rebuild-prod.yml
index e7523354..259463cd 100644
--- a/.github/workflows/manual-rebuild-prod.yml
+++ b/.github/workflows/manual-rebuild-prod.yml
@@ -36,6 +36,12 @@ jobs:
         with:
           node-version: ${{ matrix.node-version }}
 
+      # sharp@0.23.4 falls back to node-gyp; old gyp needs Python <3.11 ('rU' mode).
+      - name: Use Python 3.10 for node-gyp
+        uses: actions/setup-python@v4
+        with:
+          python-version: '3.10'
+
       - name: Build server app using Nodejs
         run: |
           docker ps
diff --git a/.github/workflows/openshift.yml b/.github/workflows/openshift.yml
index fbef581e..fd92537e 100644
--- a/.github/workflows/openshift.yml
+++ b/.github/workflows/openshift.yml
@@ -40,6 +40,12 @@ jobs:
         with:
           node-version: ${{ matrix.node-version }}
 
+      # sharp@0.23.4 falls back to node-gyp; old gyp needs Python <3.11 ('rU' mode).
+      - name: Use Python 3.10 for node-gyp
+        uses: actions/setup-python@v4
+        with:
+          python-version: '3.10'
+
       - name: Build server app using Nodejs
         run: |
           docker ps
diff --git a/.github/workflows/review.yml b/.github/workflows/review.yml
index 144a6037..89146b23 100644
--- a/.github/workflows/review.yml
+++ b/.github/workflows/review.yml
@@ -30,6 +30,12 @@ jobs:
         with:
           node-version: ${{ matrix.node-version }}
 
+      # sharp@0.23.4 falls back to node-gyp; old gyp needs Python <3.11 ('rU' mode).
+      - name: Use Python 3.10 for node-gyp
+        uses: actions/setup-python@v4
+        with:
+          python-version: '3.10'
+
       - name: Build server app using Nodejs
         run: |
           docker ps