diff --git a/.github/workflows/a3.yml b/.github/workflows/a3.yml
new file mode 100644
index 00000000000..db234113d9c
--- /dev/null
+++ b/.github/workflows/a3.yml
@@ -0,0 +1,43 @@
+name: netcdf-4.7.4_pnetcdf-12.1_ncint
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    env:
+      CC: mpicc
+      FC: mpifort
+      CPPFLAGS: "-I/home/runner/hdf5/include -I/home/runner/netcdf-c/include -I/home/runner/netcdf-fortran/include -I/home/runner/pnetcdf/include"
+      LDFLAGS: "-L/home/runner/hdf5/lib -L/home/runner/netcdf-c/lib -L/home/runner/netcdf-fortran/lib -L/home/runner/pnetcdf/lib"
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Installs
+      run: |
+        sudo apt-get install doxygen graphviz wget gfortran libjpeg-dev libz-dev
+    - name: cache-openmpi
+      id: cache-openmpi
+      uses: actions/cache@v2
+      with:
+        path: ~/openmpi
+        key: openmpi-${{ runner.os }}-4.0.4
+
+    - name: build-openmpi
+      if: steps.cache-openmpi.outputs.cache-hit != 'true'
+      run: |
+        wget https://download.open-mpi.org/release/open-mpi/v4.0/openmpi-4.0.4.tar.gz &> /dev/null
+        tar -xzf openmpi-4.0.4.tar.gz
+        pushd openmpi-4.0.4
+        ./configure --prefix=/home/runner/openmpi
+        make
+        sudo make install
+        popd
+    - name: autoreconf
+      run: autoreconf -i