diff --git a/.github/workflows/a3.yml b/.github/workflows/a3.yml
index 71e66ffd4d1..a79f3962c98 100644
--- a/.github/workflows/a3.yml
+++ b/.github/workflows/a3.yml
@@ -1,4 +1,4 @@
-name: netcdf-4.7.4_pnetcdf-12.1_ncint
+name: netcdf-4.7.4_pnetcdf-12.1_ncint_openmpi_4.0.4
 
 on:
   push:
@@ -117,9 +117,20 @@ jobs:
         make
         sudo make install
         popd
-    - name: autoreconf
-      run: autoreconf -i
-    - name: pio build
+    - name: cmake build
+      run: |
+        set -x
+        echo 'export PATH=/home/runner/openmpi/bin:$PATH' > .bashrc
+        source .bashrc
+        export CC=mpicc
+        mkdir build
+        cd build
+        export LD_LIBRARY_PATH="/home/runner/netcdf-c/lib:/home/runner/pnetcdf/lib:/home/runner/hdf5/lib:/home/runner/openmpi/lib:$LD_LIBRARY_PATH"
+        cmake -Wno-dev -DWITH_MPIEXEC='/home/runner/openmpi/bin/mpiexec;--oversubscribe' -DNetCDF_C_LIBRARY=/home/runner/netcdf-c/lib/libnetcdf.so -DNetCDF_C_INCLUDE_DIR=/home/runner/netcdf-c/include -DPnetCDF_PATH='/home/runner/pnetcdf' -DPIO_ENABLE_FORTRAN=Off -DPIO_HDF5_LOGGING=On -DPIO_USE_MALLOC=On -DPIO_ENABLE_LOGGING=On -DPIO_ENABLE_TIMING=Off .. || (cat CMakeFiles/CMakeOutput.log && cat CMakeFiles/CMakeError.log)
+        make VERBOSE=1
+        make tests VERBOSE=1
+        ctest -VV
+    - name: autotools build
       run: |
         set -x
         echo 'export PATH=/home/runner/openmpi/bin:$PATH' > .bashrc
@@ -128,8 +139,10 @@ jobs:
         source .bashrc
         export PATH="/home/runner/openmpi/bin:$PATH"
         export CC=/home/runner/openmpi/bin/mpicc
+        autoreconf -i
         ./configure --with-mpiexec='mpiexec --oversubscribe'
         which mpiexec
         make check
+
         
         
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6f1023cf9eb..d0dc010bd1c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,3 +1,9 @@
+# This is part of the PIO library.
+
+# This is the CMake build file for the main directory.
+
+# Jim Edwards
+
 cmake_minimum_required (VERSION 2.8.12)
 project (PIO C Fortran)
 #cmake_policy(VERSION 3.5.2)
@@ -16,6 +22,9 @@ set(PIO_VERSION_PATCH ${VERSION_PATCH})
 # This is needed for the libpio.settings file.
 SET(PACKAGE_VERSION ${PIO_VERSION_MAJOR}.${PIO_VERSION_MINOR}.${PIO_VERSION_PATCH})
 
+# This provides cmake_print_variables() function for debugging.
+include(CMakePrintHelpers)
+
 # Determine the configure date.
 IF(DEFINED ENV{SOURCE_DATE_EPOCH})
         EXECUTE_PROCESS(
@@ -444,10 +453,8 @@ configure_file (
   )
 
 # Configure test scripts.
-set(MPIEXEC mpiexec)
-configure_file(
-  ${CMAKE_CURRENT_SOURCE_DIR}/tests/cunit/run_tests.sh.in
-  ${CMAKE_CURRENT_BINARY_DIR}/tests/cunit/run_tests.sh @ONLY)
-configure_file(
-  ${CMAKE_CURRENT_SOURCE_DIR}/examples/c/run_tests.sh.in
-  ${CMAKE_CURRENT_BINARY_DIR}/examples/c/run_tests.sh @ONLY)
+if (NOT WITH_MPIEXEC)
+  set(WITH_MPIEXEC mpiexec)
+endif()
+set(MPIEXEC "${WITH_MPIEXEC}" CACHE INTERNAL "")
+set_property(GLOBAL PROPERTY WITH_MPIEXEC "${WITH_MPIEXEC}")
diff --git a/cmake/LibMPI.cmake b/cmake/LibMPI.cmake
index f1116724831..2fa9f52af50 100644
--- a/cmake/LibMPI.cmake
+++ b/cmake/LibMPI.cmake
@@ -1,3 +1,8 @@
+# This is part of the PIO library.
+
+# THis file contains CMake code related to MPI.
+
+# Jim Edwards
 include (CMakeParseArguments)
 
 # Find Valgrind to perform memory leak check
@@ -90,6 +95,11 @@ function (add_mpi_test TESTNAME)
     # Get the platform name
     platform_name (PLATFORM)
 
+    get_property(WITH_MPIEXEC GLOBAL PROPERTY WITH_MPIEXEC)
+    if (WITH_MPIEXEC)
+      set(MPIEXEC "${WITH_MPIEXEC}")
+    endif ()
+
     # Default ("unknown" platform) execution
     if (PLATFORM STREQUAL "unknown")
 
diff --git a/configure.ac b/configure.ac
index 63ed63e6309..1d8b48470d6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -207,9 +207,9 @@ AC_MSG_CHECKING([whether a user specified program to run mpi programs])
 AC_ARG_WITH([mpiexec],
               [AS_HELP_STRING([--with-mpiexec=<command>],
                               [Specify command to launch MPI parallel tests.])],
-            [MPIEXEC=$with_mpiexec], [MPIEXEC=mpiexec])
-AC_MSG_RESULT([$MPIEXEC])
-AC_SUBST([MPIEXEC], [$MPIEXEC])
+            [WITH_MPIEXEC=$with_mpiexec], [WITH_MPIEXEC=mpiexec])
+AC_MSG_RESULT([$WITH_MPIEXEC])
+AC_SUBST([WITH_MPIEXEC], [$WITH_MPIEXEC])
 
 # Is doxygen installed?
 AC_CHECK_PROGS([DOXYGEN], [doxygen])
diff --git a/examples/c/run_tests.sh.in b/examples/c/run_tests.sh.in
index 1caefa7585d..7651c835624 100755
--- a/examples/c/run_tests.sh.in
+++ b/examples/c/run_tests.sh.in
@@ -19,7 +19,7 @@ for EXAMPLE in $PIO_EXAMPLES
 do
     success1=false
     echo "running ${EXAMPLE}"
-    @MPIEXEC@ -n 4 ./${EXAMPLE} && success1=true
+    @WITH_MPIEXEC@ -n 4 ./${EXAMPLE} && success1=true
     if test $success1 = false; then
         break
     fi
@@ -29,7 +29,7 @@ for EXAMPLE in $PIO_EXAMPLES_16
 do
     success2=false
     echo "running ${EXAMPLE}"
-    @MPIEXEC@ -n 16 ./${EXAMPLE} && success2=true
+    @WITH_MPIEXEC@ -n 16 ./${EXAMPLE} && success2=true
     if test $success2 = false; then
         break
     fi
diff --git a/tests/cunit/run_tests.sh.in b/tests/cunit/run_tests.sh.in
index bd6e4f29215..0d322960da6 100644
--- a/tests/cunit/run_tests.sh.in
+++ b/tests/cunit/run_tests.sh.in
@@ -26,7 +26,7 @@ for TEST in $PIO_TESTS
 do
     success1=false
     echo "running ${TEST}"
-    @MPIEXEC@ -n 4 ./${TEST} && success1=true
+    @WITH_MPIEXEC@ -n 4 ./${TEST} && success1=true
     if test $success1 = false; then
         break
     fi
@@ -38,7 +38,7 @@ for TEST in $PIO_TESTS_8
 do
     success2=false
     echo "running ${TEST}"
-    @MPIEXEC@ -n 8 ./${TEST} && success2=true
+    @WITH_MPIEXEC@ -n 8 ./${TEST} && success2=true
     if test $success2 = false; then
         break
     fi