diff --git a/.github/workflows/build_mpich_source.yml b/.github/workflows/build_mpich_source.yml
index 422bd43502f..25b715693fc 100644
--- a/.github/workflows/build_mpich_source.yml
+++ b/.github/workflows/build_mpich_source.yml
@@ -1,16 +1,13 @@
 # Build MPICH from source using the latest commit on the
-# 'main' branch and cache the results. The result is compressed
-# into a 'mpich.tar' archive to preserve permissions and
-# then is uploaded as the artifact 'mpich' which can later
-# be downloaded with 'actions/download-artifact' and then
-# uncompressed with 'tar xvf mpich.tar -C <directory>'
+# 'main' branch and cache the results. The result is installed
+# to (or restored to) '${{ runner.workspace }}/mpich'.
 
 # Triggers the workflow on a call from another workflow
 on:
   workflow_call:
     inputs:
       build_mode:
-        description: "Release vs. Debug build"
+        description: "production vs. debug build"
         required: true
         type: string
 
@@ -56,8 +53,8 @@ jobs:
 
       # Enable threads=multiple for testing with Subfiling and
       # VOL connectors that require MPI_THREAD_MULTIPLE
-      - name: Install MPICH (GCC) (Release)
-        if: ${{ steps.cache-mpich-ubuntu-gcc.outputs.cache-hit != 'true' && (inputs.build_mode == 'Release') }}
+      - name: Install MPICH (GCC) (Production)
+        if: ${{ steps.cache-mpich-ubuntu-gcc.cache-hit != 'true' && (inputs.build_mode != 'debug') }}
         run: |
           cd $GITHUB_WORKSPACE/mpich
           ./autogen.sh
@@ -71,7 +68,7 @@ jobs:
       # Enable threads=multiple for testing with Subfiling and
       # VOL connectors that require MPI_THREAD_MULTIPLE
       - name: Install MPICH (GCC) (Debug)
-        if: ${{ steps.cache-mpich-ubuntu-gcc.outputs.cache-hit != 'true' && (inputs.build_mode == 'Debug') }}
+        if: ${{ steps.cache-mpich-ubuntu-gcc.cache-hit != 'true' && (inputs.build_mode == 'debug') }}
         run: |
           cd $GITHUB_WORKSPACE/mpich
           ./autogen.sh
@@ -83,13 +80,3 @@ jobs:
             --enable-threads=multiple
           make -j2
           make install
-
-      - name: Tar MPICH installation to preserve permissions for artifact
-        run: tar -cvf mpich.tar -C ${{ runner.workspace }} mpich
-
-      - name: Save MPICH installation artifact
-        uses: actions/upload-artifact@v4
-        with:
-          name: mpich
-          path: mpich.tar
-          if-no-files-found: error # 'warn' or 'ignore' are also available, defaults to `warn`
diff --git a/.github/workflows/build_openmpi_source.yml b/.github/workflows/build_openmpi_source.yml
index 0e144a0f300..a617153cc4f 100644
--- a/.github/workflows/build_openmpi_source.yml
+++ b/.github/workflows/build_openmpi_source.yml
@@ -1,16 +1,13 @@
 # Build OpenMPI from source using the latest commit on the
-# 'main' branch and cache the results. The result is compressed
-# into a 'openmpi.tar' archive to preserve permissions and
-# then is uploaded as the artifact 'openmpi' which can later
-# be downloaded with 'actions/download-artifact' and then
-# uncompressed with 'tar xvf openmpi.tar -C <directory>'
+# 'main' branch and cache the results. The result is installed
+# to (or restored to) '${{ runner.workspace }}/openmpi'.
 
 # Triggers the workflow on a call from another workflow
 on:
   workflow_call:
     inputs:
       build_mode:
-        description: "Release vs. Debug build"
+        description: "production vs. debug build"
         required: true
         type: string
 
@@ -54,8 +51,8 @@ jobs:
           path: ${{ runner.workspace }}/openmpi
           key: ${{ runner.os }}-${{ runner.arch }}-gcc-openmpi-${{ steps.get-sha.outputs.sha }}-${{ inputs.build_mode }}
 
-      - name: Install OpenMPI (GCC) (Release)
-        if: ${{ steps.cache-openmpi-ubuntu-gcc.outputs.cache-hit != 'true' && (inputs.build_mode == 'Release') }}
+      - name: Install OpenMPI (GCC) (Production)
+        if: ${{ steps.cache-openmpi-ubuntu-gcc.cache-hit != 'true' && (inputs.build_mode != 'debug') }}
         run: |
           cd $GITHUB_WORKSPACE/ompi
           ./autogen.pl
@@ -66,7 +63,7 @@ jobs:
           make install
 
       - name: Install OpenMPI (GCC) (Debug)
-        if: ${{ steps.cache-openmpi-ubuntu-gcc.outputs.cache-hit != 'true' && (inputs.build_mode == 'Debug') }}
+        if: ${{ steps.cache-openmpi-ubuntu-gcc.cache-hit != 'true' && (inputs.build_mode == 'debug') }}
         run: |
           cd $GITHUB_WORKSPACE/ompi
           ./autogen.pl
@@ -76,13 +73,3 @@ jobs:
             --enable-debug
           make -j2
           make install
-
-      - name: Tar OpenMPI installation to preserve permissions for artifact
-        run: tar -cvf openmpi.tar -C ${{ runner.workspace }} openmpi
-
-      - name: Save OpenMPI installation artifact
-        uses: actions/upload-artifact@v4
-        with:
-          name: openmpi
-          path: openmpi.tar
-          if-no-files-found: error # 'warn' or 'ignore' are also available, defaults to `warn`