diff --git a/.github/workflows/cmake.yaml b/.github/workflows/cmake.yaml
index d3eeee0bd..99db098d8 100644
--- a/.github/workflows/cmake.yaml
+++ b/.github/workflows/cmake.yaml
@@ -21,11 +21,42 @@ jobs:
           cache: 'pip'
       - run: pip install pytest numpy colorama
 
-      - uses: awalsh128/cache-apt-pkgs-action@latest
+      # using a stable action version instead of latest to create/restore cache for now
+      - uses: awalsh128/cache-apt-pkgs-action@v1.6.1
         with:
           packages: libhdf5-dev qtbase5-dev qt5-qmake libqt5svg5-dev libpng-dev libtiff-dev libfmt-dev
           version: 1.0
 
+      # verify packages restored from cache are installed.
+      # This catches incomplete apt installs after cache restore.
+      - name: Verify apt packages
+        id: verify_packages
+        run: |
+          failed=""
+
+          for pkg in \
+            libhdf5-dev \
+            qtbase5-dev \
+            qt5-qmake \
+            libqt5svg5-dev \
+            libpng-dev \
+            libtiff-dev \
+            libfmt-dev
+          do
+            if ! dpkg -s "$pkg" >/dev/null 2>&1; then
+              echo "Missing: $pkg"
+              failed="$failed $pkg"
+            fi
+          done
+
+
+          if [ -n "$failed" ]; then
+            echo "Missing packages after cache restore: $failed. Try deleting the cache and rerunning the workflow."
+            exit 1
+          else
+            echo "All apt packages are installed"  
+          fi
+
       - name: Configure CMake
         # Configure CMake in a 'build' subdirectory. `CMAKE_BUILD_TYPE` is only required if you are using a single-configuration generator such as make.
         # See https://cmake.org/cmake/help/latest/variable/CMAKE_BUILD_TYPE.html?highlight=cmake_build_type
diff --git a/.github/workflows/run_tests.yaml b/.github/workflows/run_tests.yaml
index 96d04205e..138d32e7e 100644
--- a/.github/workflows/run_tests.yaml
+++ b/.github/workflows/run_tests.yaml
@@ -20,11 +20,37 @@ jobs:
           cache: 'pip'
       - run: pip install pytest numpy colorama pyzmq
 
-      - uses: awalsh128/cache-apt-pkgs-action@latest
+      # using a stable action version instead of latest to create/restore cache for now
+      - uses: awalsh128/cache-apt-pkgs-action@v1.6.1
         with:
           packages: libhdf5-dev libfmt-dev
           version: 1.0
 
+      # verify packages restored from cache are installed.
+      # This catches incomplete apt installs after cache restore.
+      - name: Verify apt packages
+        id: verify_packages
+        run: |
+          failed=""
+
+          for pkg in \
+            libhdf5-dev \
+            libfmt-dev
+          do
+            if ! dpkg -s "$pkg" >/dev/null 2>&1; then
+              echo "Missing: $pkg"
+              failed="$failed $pkg"
+            fi
+          done
+
+          if [ -n "$failed" ]; then
+            echo "Missing packages after cache restore: $failed. Try deleting the cache and rerunning the workflow."
+            exit 1
+          else
+            echo "All apt packages are installed"  
+          fi
+
+
       - name: Configure CMake
         run: |
           cmake -B ${{github.workspace}}/build \