diff --git a/.github/scripts/test.sh b/.github/scripts/test.sh
index d5bac2c520..86119da873 100755
--- a/.github/scripts/test.sh
+++ b/.github/scripts/test.sh
@@ -1,80 +1,22 @@
 #!/bin/bash
-
-# Catch INT to kill subprocesses
-trap end_make INT
-
 DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
 
-if [ -z ${MACH} ]; then
-    echo "Please define MACH" 1>&2
-    exit 1
-fi
-
-ERR=0
-MATS=${MACH}/mats
-SUMMARYFILE=${MACH}/summary
-declare -a PIDS
-
-# Clean and create summary file
-rm -f "${SUMMARYFILE}"
-touch "${SUMMARYFILE}"
-
-end_make() {
-    echo "Caught Ctrl-C" 1>&2
-    for i in "${!PIDS[@]}"; do
-        local pid="${PID[$i]}"
-        echo "Killing pid ${pid}" 1>&2
-        kill ${pid}
-        rm -r "${MATS}"."${i}"
-    done
-    exit 1
-}
-
 runmats() {
-    local id=$1
-    local matsdest="${MATS}.${id}"
-    cp -r "${MATS}" "${matsdest}"
-    echo make allxhelp "${@:2}"
-
-    # Use -l here so we don't overload machines with less than the number
-    # of parallel tests we force to run
-    make -l$(nproc) -C "${matsdest}" allxhelp "${@:2}" 2>&1 | tee -a Make.out | grep '^matting ' &
-    PIDS[$id]="$!"
+  echo make allxhelp "$@"
+  make -C ${MACH}/mats allxhelp "$@" 2>&1 | tee -a Make.out | grep '^matting '
 }
 
-ARGS=("o=0"
-      "o=0 cp0=t"
-      "o=3"
-      "o=3 cp0=t"
-      "o=3 cp0=t eval=interpret")
+# Split these out so that we get output every 10 minutes on Windows builds.
+runmats o=0
+runmats o=0 cp0=t
+runmats o=3
+runmats o=3 cp0=t
+runmats o=3 cp0=t eval=interpret
 
-# Run all test classes in parallel
-for i in ${!ARGS[@]}; do
-    runmats $i ${ARGS[$i]}
-done
-
-# Wait for all jobs
-for i in "${!PIDS[@]}"; do
-    pid="${PIDS[$i]}"
-    wait "${pid}"
-
-    # Append current contents to final summary file
-    if [ -f "${MATS}.${i}/summary" ]; then
-        cat "${MATS}.${i}/summary" >> "${SUMMARYFILE}"
-    else
-        echo "ERROR: No summary file for mats.${i}" 1>&2
-        end_make
-        ERR=1
-    fi
-done
-
-# All done - sort lines of file for comparison
-sort "${SUMMARYFILE}" > "${SUMMARYFILE}.sorted"
-
-if [[ "${ERR}" = "1" ]]; then
-    exit 1
+if [ -f ${MACH}/mats/summary ]; then
+  cat ${MACH}/mats/summary
+  diff -q ${DIR}/summary ${MACH}/mats/summary
+  exit $?
 else
-    cat "${SUMMARYFILE}"
-    diff -q ${DIR}/summary "${SUMMARYFILE}.sorted"    
-    exit $?
+  exit 1
 fi