From 9eab1695fafcf82b5434efb633cc0a07a91a9c69 Mon Sep 17 00:00:00 2001
From: John Vincent Cauilan <64677361+johvincau@users.noreply.github.com>
Date: Wed, 1 Jul 2026 18:29:58 -0500
Subject: [PATCH 1/6] Add cache key script and caching steps for NJOY, MOAB,
 DAGMC, libmesh

---
 .github/workflows/ci.yml        | 71 +++++++++++++++++++++++++--------
 tools/ci/gha-cache-keys.sh      | 18 +++++++++
 tools/ci/gha-install-libmesh.sh |  2 +
 tools/ci/gha-install-njoy.sh    |  1 +
 tools/ci/gha-install.sh         | 18 ++++++---
 5 files changed, 88 insertions(+), 22 deletions(-)
 create mode 100755 tools/ci/gha-cache-keys.sh

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index c3da79c0482..2a9cd710ac8 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -110,6 +110,9 @@ jobs:
         uses: actions/setup-python@v6
         with:
           python-version: ${{ matrix.python-version }}
+#          cache: 'pip' # caching pip dependencies
+#          cache-dependency-path: |
+#            requirements-pip.txt
 
       - name: Environment Variables
         run: |
@@ -146,6 +149,51 @@ jobs:
           sudo update-alternatives --set mpirun /usr/bin/mpirun.mpich
           sudo update-alternatives --set mpi-x86_64-linux-gnu /usr/include/x86_64-linux-gnu/mpich
 
+      - name: cache-xs
+        uses: actions/cache@v6
+        with:
+          path: |
+            ~/nndc_hdf5
+            ~/endf-b-vii.1
+          key: ${{ runner.os }}-build-xs-cache-${{ hashFiles(format('{0}/tools/ci/download-xs.sh', github.workspace)) }}
+
+      - name: Get dependency cache keys
+        shell: bash
+        run: $GITHUB_WORKSPACE/tools/ci/gha-cache-keys.sh
+
+      - name: Restore NJOY2016
+        uses: actions/cache@v6
+        with:
+          path: |
+            ~/NJOY2016/metaconfigure
+            ~/NJOY2016/build/njoy
+            ~/NJOY2016/build/libnjoy.so
+          key: NJOY2016-${{ env.NJOY_HASH }} 
+
+      - name: Restore MOAB
+        if: ${{ matrix.dagmc == 'y' }}
+        uses: actions/cache@v6
+        with:
+          path: |
+            ~/MOAB
+          key: MOAB-${{ env.MOAB_HASH }}
+        
+      - name: Restore DAGMC
+        if: ${{ matrix.dagmc == 'y' }}
+        uses: actions/cache@v6
+        with:
+          path: |
+            ~/DAGMC
+          key: DAGMC-${{ env.DAGMC_HASH }}
+
+      - name: Restore libmesh
+        if: ${{ matrix.libmesh == 'y' }} 
+        uses: actions/cache@v6
+        with:
+          path: |
+            ~/LIBMESH
+          key: libmesh-mpi-${{matrix.mpi}}-${{ env.LB_HASH }} 
+
       - name: install
         shell: bash
         run: |
@@ -154,16 +202,7 @@ jobs:
 
       - name: display-config
         shell: bash
-        run: |
-          openmc -v
-
-      - name: cache-xs
-        uses: actions/cache@v5
-        with:
-          path: |
-            ~/nndc_hdf5
-            ~/endf-b-vii.1
-          key: ${{ runner.os }}-build-xs-cache-${{ hashFiles(format('{0}/tools/ci/download-xs.sh', github.workspace)) }}
+        run: openmc -v
 
       - name: before
         shell: bash
@@ -174,13 +213,13 @@ jobs:
         run: |
           CTEST_OUTPUT_ON_FAILURE=1 make test -C $GITHUB_WORKSPACE/build/
           $GITHUB_WORKSPACE/tools/ci/gha-script.sh
-
+ 
       - name: Setup tmate debug session
         continue-on-error: true
         if: ${{ failure() && contains(env.COMMIT_MESSAGE, '[gha-debug]') }}
         uses: mxschmitt/action-tmate@v3
         timeout-minutes: 10
-
+ 
       - name: Generate C++ coverage (gcovr)
         shell: bash
         run: |
@@ -198,13 +237,13 @@ jobs:
             --merge-mode-functions=separate \
             --print-summary \
             --lcov -o coverage-cpp.lcov || true
-
+ 
       - name: Merge C++ and Python coverage
         shell: bash
         run: |
           # Merge C++ and Python LCOV into a single file for upload
           cat coverage-cpp.lcov coverage-python.lcov > coverage.lcov
-
+ 
       - name: Upload coverage to Coveralls
         if: ${{ hashFiles('coverage.lcov') != '' }}
         uses: coverallsapp/github-action@v2
@@ -214,7 +253,7 @@ jobs:
           flag-name: C++ and Python
           path-to-lcov: coverage.lcov
           fail-on-error: false
-
+ 
   coverage:
     needs: [filter-changes, main]
     if: ${{ always() }}
@@ -227,7 +266,7 @@ jobs:
           github-token: ${{ secrets.GITHUB_TOKEN }}
           parallel-finished: true
           fail-on-error: false
-
+ 
   ci-pass:
     needs: [filter-changes, main, coverage]
     name: Check CI status
diff --git a/tools/ci/gha-cache-keys.sh b/tools/ci/gha-cache-keys.sh
new file mode 100755
index 00000000000..724ed562663
--- /dev/null
+++ b/tools/ci/gha-cache-keys.sh
@@ -0,0 +1,18 @@
+#!/bin/bash
+set -ex
+
+echo "NJOY_HASH=$(git ls-remote https://github.com/njoy/NJOY2016.git HEAD \
+    --branch 2016.78 | head -c 15)" >> $GITHUB_ENV
+
+if [[ "$DAGMC" == 'y' ]]; then
+    echo "MOAB_HASH=$(git ls-remote https://bitbucket.org/fathomteam/moab.git \
+    --branch Version5.1.0 HEAD | head -c 15)" >> $GITHUB_ENV
+
+    echo "DAGMC_HASH=$(git ls-remote https://github.com/svalinn/dagmc.git HEAD |\
+    head -c 15)" >> $GITHUB_ENV
+fi
+
+if [[ "$LIBMESH" == 'y' ]]; then
+    echo "LB_HASH=$(git ls-remote https://github.com/libmesh/libmesh \
+    --branch v1.7.1 HEAD | head -c 15)" >> $GITHUB_ENV
+fi
\ No newline at end of file
diff --git a/tools/ci/gha-install-libmesh.sh b/tools/ci/gha-install-libmesh.sh
index d4557d2d3a2..a6486799bca 100755
--- a/tools/ci/gha-install-libmesh.sh
+++ b/tools/ci/gha-install-libmesh.sh
@@ -17,5 +17,7 @@ else
 fi
 make -j4 install
 rm -rf $HOME/LIBMESH/build
+rm -rf $HOME/LIBMESH/libmesh
+rm -rf $HOME/LIBMESH/examples
 
 popd
diff --git a/tools/ci/gha-install-njoy.sh b/tools/ci/gha-install-njoy.sh
index 168fcd4a7b7..071d7ad3a03 100755
--- a/tools/ci/gha-install-njoy.sh
+++ b/tools/ci/gha-install-njoy.sh
@@ -5,3 +5,4 @@ git clone -b 2016.78 https://github.com/njoy/NJOY2016
 cd NJOY2016
 mkdir build && cd build
 cmake -Dstatic=on .. && make 2>/dev/null && sudo make install
+rm -rf $HOME/NJOY2016/build
\ No newline at end of file
diff --git a/tools/ci/gha-install.sh b/tools/ci/gha-install.sh
index 4cf62afbb71..e164ad5b663 100755
--- a/tools/ci/gha-install.sh
+++ b/tools/ci/gha-install.sh
@@ -7,11 +7,15 @@ pip install --upgrade pytest
 pip install --upgrade numpy
 
 # Install NJOY 2016
-./tools/ci/gha-install-njoy.sh
+if [[ ! -d "$HOME/NJOY2016" ]]; then
+    ./tools/ci/gha-install-njoy.sh
+fi
 
 # Install DAGMC if needed
-if [[ $DAGMC = 'y' ]]; then
-    ./tools/ci/gha-install-dagmc.sh
+if [[ "$DAGMC" == "y" ]]; then
+    if [[ ! -d "$HOME/DAGMC" ]] || [[ ! -d "$HOME/MOAB" ]]; then
+        ./tools/ci/gha-install-dagmc.sh
+    fi
 fi
 
 # Install NCrystal and verify installation
@@ -19,8 +23,10 @@ pip install 'ncrystal>=4.1.0'
 nctool --test
 
 # Install libMesh if needed
-if [[ $LIBMESH = 'y' ]]; then
-    ./tools/ci/gha-install-libmesh.sh
+if [[ "$LIBMESH" == "y" ]]; then
+    if [[ ! -d "$HOME/LIBMESH" ]]; then
+        ./tools/ci/gha-install-libmesh.sh
+    fi
 fi
 
 # Install MCPL
@@ -28,7 +34,7 @@ pip install mcpl
 
 # For MPI configurations, make sure mpi4py and h5py are built against the
 # correct version of MPI
-if [[ $MPI == 'y' ]]; then
+if [[ "$MPI" == "y" ]]; then
     pip install --no-binary=mpi4py mpi4py
 
     export CC=mpicc

From a404973377656a6249437e69977ff9450db93a54 Mon Sep 17 00:00:00 2001
From: John Vincent Cauilan <64677361+johvincau@users.noreply.github.com>
Date: Thu, 2 Jul 2026 20:26:27 -0500
Subject: [PATCH 2/6] Add pip requirements caching for expensive wheels

---
 .github/workflows/ci.yml  |  6 +++---
 tools/ci/requirements.txt | 18 ++++++++++++++++++
 2 files changed, 21 insertions(+), 3 deletions(-)
 create mode 100755 tools/ci/requirements.txt

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2a9cd710ac8..b80d254d675 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -110,9 +110,9 @@ jobs:
         uses: actions/setup-python@v6
         with:
           python-version: ${{ matrix.python-version }}
-#          cache: 'pip' # caching pip dependencies
-#          cache-dependency-path: |
-#            requirements-pip.txt
+          cache: 'pip' 
+          cache-dependency-path: |
+            $GITHUB_WORKSPACE/tools/ci/requirements.txt
 
       - name: Environment Variables
         run: |
diff --git a/tools/ci/requirements.txt b/tools/ci/requirements.txt
new file mode 100755
index 00000000000..8a53cd39e1d
--- /dev/null
+++ b/tools/ci/requirements.txt
@@ -0,0 +1,18 @@
+numpy
+h5py
+scipy
+ipython
+matplotlib
+pandas
+lxml
+uncertainties
+endf
+packaging
+pytest
+pytest-cov>=4.0
+pytest-rerunfailures
+colorama
+openpyxl
+coverage>=7.4
+gcovr>=7.2
+mpi4py
\ No newline at end of file

From f4094ff8fc9a5ad16500f5482d105730492cdef1 Mon Sep 17 00:00:00 2001
From: John Vincent Cauilan <64677361+johvincau@users.noreply.github.com>
Date: Sat, 4 Jul 2026 16:03:28 -0500
Subject: [PATCH 3/6] Specify pinned versions for NJOY, MOAB, and LIBMESH

---
 tools/ci/gha-cache-keys.sh | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/ci/gha-cache-keys.sh b/tools/ci/gha-cache-keys.sh
index 724ed562663..97f731ba3b7 100755
--- a/tools/ci/gha-cache-keys.sh
+++ b/tools/ci/gha-cache-keys.sh
@@ -2,11 +2,11 @@
 set -ex
 
 echo "NJOY_HASH=$(git ls-remote https://github.com/njoy/NJOY2016.git HEAD \
-    --branch 2016.78 | head -c 15)" >> $GITHUB_ENV
+    --tags 2016.78 | head -c 15)" >> $GITHUB_ENV
 
 if [[ "$DAGMC" == 'y' ]]; then
     echo "MOAB_HASH=$(git ls-remote https://bitbucket.org/fathomteam/moab.git \
-    --branch Version5.1.0 HEAD | head -c 15)" >> $GITHUB_ENV
+    --tags Version5.1.0 | head -c 15)" >> $GITHUB_ENV
 
     echo "DAGMC_HASH=$(git ls-remote https://github.com/svalinn/dagmc.git HEAD |\
     head -c 15)" >> $GITHUB_ENV
@@ -14,5 +14,5 @@ fi
 
 if [[ "$LIBMESH" == 'y' ]]; then
     echo "LB_HASH=$(git ls-remote https://github.com/libmesh/libmesh \
-    --branch v1.7.1 HEAD | head -c 15)" >> $GITHUB_ENV
+    --tags v1.7.1 | head -c 15)" >> $GITHUB_ENV
 fi
\ No newline at end of file

From e56a8bea0d7bfb26ba25c90ab860711f66b17eec Mon Sep 17 00:00:00 2001
From: John Vincent Cauilan <64677361+johvincau@users.noreply.github.com>
Date: Tue, 7 Jul 2026 16:22:38 -0500
Subject: [PATCH 4/6] Split pip cache key depending on mpi-dep version

---
 .github/workflows/ci.yml                      | 20 ++++++++++---------
 tools/ci/gha-cache-keys.sh                    | 11 ++++++++++
 ...equirements.txt => requirements-mpi-n.txt} |  4 ++--
 tools/ci/requirements-mpi-y.txt               |  7 +++++++
 4 files changed, 31 insertions(+), 11 deletions(-)
 rename tools/ci/{requirements.txt => requirements-mpi-n.txt} (81%)
 create mode 100755 tools/ci/requirements-mpi-y.txt

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b80d254d675..e839ed3644d 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -106,14 +106,6 @@ jobs:
         with:
           fetch-depth: 0
 
-      - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v6
-        with:
-          python-version: ${{ matrix.python-version }}
-          cache: 'pip' 
-          cache-dependency-path: |
-            $GITHUB_WORKSPACE/tools/ci/requirements.txt
-
       - name: Environment Variables
         run: |
           echo "OPENMC_CROSS_SECTIONS=$HOME/nndc_hdf5/cross_sections.xml" >> $GITHUB_ENV
@@ -157,10 +149,20 @@ jobs:
             ~/endf-b-vii.1
           key: ${{ runner.os }}-build-xs-cache-${{ hashFiles(format('{0}/tools/ci/download-xs.sh', github.workspace)) }}
 
-      - name: Get dependency cache keys
+      - name: Get dependency cache keys and mpi-dep versions
         shell: bash
         run: $GITHUB_WORKSPACE/tools/ci/gha-cache-keys.sh
 
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v6
+        with:
+          python-version: ${{ matrix.python-version }}
+          cache: 'pip' 
+          cache-dependency-path: |
+            $GITHUB_WORKSPACE/tools/ci/mpi-deps.txt
+            $GITHUB_WORKSPACE/tools/ci/requirements-mpi-${{ matrix.mpi }}.txt
+            
+
       - name: Restore NJOY2016
         uses: actions/cache@v6
         with:
diff --git a/tools/ci/gha-cache-keys.sh b/tools/ci/gha-cache-keys.sh
index 97f731ba3b7..4f696ed0287 100755
--- a/tools/ci/gha-cache-keys.sh
+++ b/tools/ci/gha-cache-keys.sh
@@ -15,4 +15,15 @@ fi
 if [[ "$LIBMESH" == 'y' ]]; then
     echo "LB_HASH=$(git ls-remote https://github.com/libmesh/libmesh \
     --tags v1.7.1 | head -c 15)" >> $GITHUB_ENV
+fi
+
+if [[ "$MPI" == 'y' ]]; then
+    dpkg-query -W libmpich-dev libhdf5-mpich-dev > $GITHUB_WORKSPACE/tools/ci/mpi-deps.txt
+    cat $GITHUB_WORKSPACE/tools/ci/mpi-deps.txt
+    sha256sum $GITHUB_WORKSPACE/tools/ci/requirements-mpi-y.txt
+    sha256sum $GITHUB_WORKSPACE/tools/ci/mpi-deps.txt
+else
+    touch $GITHUB_WORKSPACE/tools/ci/mpi-deps.txt
+    sha256sum $GITHUB_WORKSPACE/tools/ci/requirements-mpi-n.txt
+    sha256sum $GITHUB_WORKSPACE/tools/ci/mpi-deps.txt
 fi
\ No newline at end of file
diff --git a/tools/ci/requirements.txt b/tools/ci/requirements-mpi-n.txt
similarity index 81%
rename from tools/ci/requirements.txt
rename to tools/ci/requirements-mpi-n.txt
index 8a53cd39e1d..f5aecc94d0c 100755
--- a/tools/ci/requirements.txt
+++ b/tools/ci/requirements-mpi-n.txt
@@ -1,3 +1,4 @@
+# requirements-mpi-n.txt
 numpy
 h5py
 scipy
@@ -14,5 +15,4 @@ pytest-rerunfailures
 colorama
 openpyxl
 coverage>=7.4
-gcovr>=7.2
-mpi4py
\ No newline at end of file
+gcovr>=7.2
\ No newline at end of file
diff --git a/tools/ci/requirements-mpi-y.txt b/tools/ci/requirements-mpi-y.txt
new file mode 100755
index 00000000000..e6d0b96750c
--- /dev/null
+++ b/tools/ci/requirements-mpi-y.txt
@@ -0,0 +1,7 @@
+# requirements-mpi-y.txt
+-r requirements-mpi-n.txt
+mpi4py
+setuptools
+Cython
+pkgconfig
+h5py
\ No newline at end of file

From 563fa0f795640904c3112c03b58ab779289f3a7f Mon Sep 17 00:00:00 2001
From: John Vincent Cauilan <64677361+johvincau@users.noreply.github.com>
Date: Tue, 7 Jul 2026 18:25:46 -0500
Subject: [PATCH 5/6] Revert to manual pip caching for control over key

---
 .github/workflows/ci.yml | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index e839ed3644d..3fcec8f380b 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -106,6 +106,11 @@ jobs:
         with:
           fetch-depth: 0
 
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v6
+        with:
+          python-version: ${{ matrix.python-version }}
+
       - name: Environment Variables
         run: |
           echo "OPENMC_CROSS_SECTIONS=$HOME/nndc_hdf5/cross_sections.xml" >> $GITHUB_ENV
@@ -153,15 +158,11 @@ jobs:
         shell: bash
         run: $GITHUB_WORKSPACE/tools/ci/gha-cache-keys.sh
 
-      - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v6
+      - name: Restore pip cache according to mpi-deps
+        uses: actions/cache@v6
         with:
-          python-version: ${{ matrix.python-version }}
-          cache: 'pip' 
-          cache-dependency-path: |
-            $GITHUB_WORKSPACE/tools/ci/mpi-deps.txt
-            $GITHUB_WORKSPACE/tools/ci/requirements-mpi-${{ matrix.mpi }}.txt
-            
+          path: ~/.cache/pip
+          key: pip-${{ runner.os }}-py${{ matrix.python-version }}-mpi-${{ matrix.mpi }}-${{ hashFiles(format('{0}/tools/ci/requirements*.txt', github.workspace)) }}-${{ hashFiles(format('{0}/tools/ci/mpi-deps.txt', github.workspace)) }}
 
       - name: Restore NJOY2016
         uses: actions/cache@v6

From bf7468a619cbaf235427c0823b84e57172ab8410 Mon Sep 17 00:00:00 2001
From: John Vincent Cauilan <64677361+johvincau@users.noreply.github.com>
Date: Wed, 8 Jul 2026 14:46:43 -0500
Subject: [PATCH 6/6] Configure pip key gen to use either
 requirements-mpi-y/n.txt

---
 .github/workflows/ci.yml | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 3fcec8f380b..4d129df1fad 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -162,7 +162,8 @@ jobs:
         uses: actions/cache@v6
         with:
           path: ~/.cache/pip
-          key: pip-${{ runner.os }}-py${{ matrix.python-version }}-mpi-${{ matrix.mpi }}-${{ hashFiles(format('{0}/tools/ci/requirements*.txt', github.workspace)) }}-${{ hashFiles(format('{0}/tools/ci/mpi-deps.txt', github.workspace)) }}
+          key: pip-${{ runner.os }}-py${{ matrix.python-version }}-mpi-${{ matrix.mpi }}-${{ hashFiles(format('tools/ci/requirements-mpi-{0}.txt', matrix.mpi)) }}-${{ hashFiles('tools/ci/mpi-deps.txt') }}
+
 
       - name: Restore NJOY2016
         uses: actions/cache@v6