diff --git a/.github/actions/Nightly_01_DirectorySetup/action.yaml b/.github/actions/Nightly_01_DirectorySetup/action.yaml
new file mode 100644
index 000000000..5bcf5051c
--- /dev/null
+++ b/.github/actions/Nightly_01_DirectorySetup/action.yaml
@@ -0,0 +1,18 @@
+name: Nightly 01 Directory Setup
+
+runs:
+  using: "composite"
+  steps:
+  - name: Nightly 01 Directory Setup
+    shell: bash
+    run: |
+      # Write RUNID to file so that following steps use the
+      # same date and don't pick up the next day's date
+      RUNID=`date +"%Y%m%d"`
+      echo "${RUNID}" > RUNID_SAVE.log
+      # Get day of week for later use and write to file
+      DOW=$(date +%u)
+      echo "${DOW}" > DOW_SAVE.log
+      #
+      cd util/weekly_build
+      ./01_DirectorySetup.sh ${RUNID} ${BASEDIR} ${PLATFORM}
diff --git a/.github/actions/Nightly_02_GetSpackStack/action.yaml b/.github/actions/Nightly_02_GetSpackStack/action.yaml
new file mode 100644
index 000000000..268adaf29
--- /dev/null
+++ b/.github/actions/Nightly_02_GetSpackStack/action.yaml
@@ -0,0 +1,11 @@
+name: Nightly 02 Get Spack-Stack
+
+runs:
+  using: "composite"
+  steps:
+  - name: Nightly 02 Get Spack-Stack
+    shell: bash
+    run: |
+      RUNID=$(<RUNID_SAVE.log)
+      cd util/weekly_build
+      ./02_GetSpackStack.sh ${RUNID} ${BASEDIR} ${PLATFORM}
diff --git a/.github/actions/Nightly_03_SetupEnv/action.yaml b/.github/actions/Nightly_03_SetupEnv/action.yaml
new file mode 100644
index 000000000..ef44b9e80
--- /dev/null
+++ b/.github/actions/Nightly_03_SetupEnv/action.yaml
@@ -0,0 +1,11 @@
+name: Nightly 03 Setup Env
+
+runs:
+  using: "composite"
+  steps:
+  - name: Nightly 03 Setup Env
+    shell: bash
+    run: |
+      RUNID=$(<RUNID_SAVE.log)
+      cd util/weekly_build
+      ./03_SetupEnv.sh ${RUNID} ${BASEDIR} ${PLATFORM}
diff --git a/.github/actions/Nightly_04_SpackInstall/action.yaml b/.github/actions/Nightly_04_SpackInstall/action.yaml
new file mode 100644
index 000000000..b6472ccda
--- /dev/null
+++ b/.github/actions/Nightly_04_SpackInstall/action.yaml
@@ -0,0 +1,20 @@
+name: Nightly 04 Spack Install
+
+runs:
+  using: "composite"
+  steps:
+  - name: Nightly 04 Spack Install
+    shell: bash
+    run: |
+      RUNID=$(<RUNID_SAVE.log)
+      DOW=$(<DOW_SAVE.log)
+      # Build everything from scratch on Sundays, otherwise
+      # use build cache to speed up the installations.
+      # Monday is 1 ... Sunday is 7
+      if [[ $DOW == 7 ]]; then
+        export REUSE_BUILD_CACHE="NO"
+      else
+        export REUSE_BUILD_CACHE="YES"
+      fi
+      cd util/weekly_build
+      ./04_SpackInstall.sh ${RUNID} ${BASEDIR} ${PLATFORM}
diff --git a/.github/actions/Nightly_05_BuildCache/action.yaml b/.github/actions/Nightly_05_BuildCache/action.yaml
new file mode 100644
index 000000000..b73505c37
--- /dev/null
+++ b/.github/actions/Nightly_05_BuildCache/action.yaml
@@ -0,0 +1,11 @@
+name: Nightly 05 Build Cache
+
+runs:
+  using: "composite"
+  steps:
+  - name: Nightly 05 Build Cache
+    shell: bash
+    run: |
+      RUNID=$(<RUNID_SAVE.log)
+      cd util/weekly_build
+      ./05_BuildCache.sh ${RUNID} ${BASEDIR} ${PLATFORM}
diff --git a/.github/actions/Nightly_07_Cleanup/action.yaml b/.github/actions/Nightly_07_Cleanup/action.yaml
new file mode 100644
index 000000000..53fee8000
--- /dev/null
+++ b/.github/actions/Nightly_07_Cleanup/action.yaml
@@ -0,0 +1,11 @@
+name: Nightly 07 Cleanup
+
+runs:
+  using: "composite"
+  steps:
+  - name: Nightly 07 Cleanup
+    shell: bash
+    run: |
+      RUNID=$(<RUNID_SAVE.log)
+      cd util/weekly_build
+      ./05_BuildCache.sh ${RUNID} ${BASEDIR} ${PLATFORM}
diff --git a/configs/sites/tier1/acorn/compilers.yaml b/configs/sites/tier1/acorn/compilers.yaml
index 179fcbdbf..7e63ca9c2 100644
--- a/configs/sites/tier1/acorn/compilers.yaml
+++ b/configs/sites/tier1/acorn/compilers.yaml
@@ -6,10 +6,7 @@ compilers:
       cxx: CC
       f77: ftn
       fc: ftn
-    flags:
-      cflags: -static-libgcc -static-libstdc++ -Bstatic -lstdc++ -Bdynamic -lm -lpthread
-      cxxflags: -static-libgcc -static-libstdc++ -Bstatic -lstdc++ -Bdynamic -lm -lpthread
-      fflags: -static-libgcc -static-libstdc++ -Bstatic -lstdc++ -Bdynamic -lm -lpthread
+    flags: {}
     operating_system: sles15
     modules:
     - PrgEnv-intel/8.5.0
@@ -30,10 +27,7 @@ compilers:
       cxx: CC
       f77: ftn
       fc: ftn
-    flags:
-      cflags: -static-libgcc -static-libstdc++ -Bstatic -lstdc++ -Bdynamic -lm -lpthread
-      cxxflags: -static-libgcc -static-libstdc++ -Bstatic -lstdc++ -Bdynamic -lm -lpthread
-      fflags: -static-libgcc -static-libstdc++ -Bstatic -lstdc++ -Bdynamic -lm -lpthread
+    flags: {}
     operating_system: sles15
     modules:
     - PrgEnv-intel/8.5.0
diff --git a/configs/sites/tier1/acorn/mirrors.yaml b/configs/sites/tier1/acorn/mirrors.yaml
new file mode 100644
index 000000000..366f74171
--- /dev/null
+++ b/configs/sites/tier1/acorn/mirrors.yaml
@@ -0,0 +1,3 @@
+mirrors:
+  local-source: file:///lfs/h1/emc/nceplibs/noscrub/spack-stack/cache
+  local-binary: file:///lfs/h1/emc/nceplibs/noscrub/spack-stack/cache
diff --git a/configs/sites/tier1/atlantis/mirrors.yaml b/configs/sites/tier1/atlantis/mirrors.yaml
index 4d363e009..d2371749e 100644
--- a/configs/sites/tier1/atlantis/mirrors.yaml
+++ b/configs/sites/tier1/atlantis/mirrors.yaml
@@ -1,18 +1,3 @@
 mirrors:
-  local-source:
-    fetch:
-      url: file:///neptune_diagnostics/spack-stack/source-cache/
-      access_pair:
-      - null
-      - null
-      access_token: null
-      profile: null
-      endpoint_url: null
-    push:
-      url: file:///neptune_diagnostics/spack-stack/source-cache/
-      access_pair:
-      - null
-      - null
-      access_token: null
-      profile: null
-      endpoint_url: null
+  local-source: file:///neptune_diagnostics/spack-stack/source-cache
+  local-binary: file:///neptune_diagnostics/spack-stack/build-cache
diff --git a/configs/sites/tier1/narwhal/mirrors.yaml b/configs/sites/tier1/narwhal/mirrors.yaml
index 2b67bea03..5b06fc3fb 100644
--- a/configs/sites/tier1/narwhal/mirrors.yaml
+++ b/configs/sites/tier1/narwhal/mirrors.yaml
@@ -1,18 +1,3 @@
 mirrors:
-  local-source:
-    fetch:
-      url: file:///p/cwfs/projects/NEPTUNE/spack-stack/source-cache
-      access_pair:
-      - null
-      - null
-      access_token: null
-      profile: null
-      endpoint_url: null
-    push:
-      url: file:///p/cwfs/projects/NEPTUNE/spack-stack/source-cache
-      access_pair:
-      - null
-      - null
-      access_token: null
-      profile: null
-      endpoint_url: null
+  local-source: file:///p/cwfs/projects/NEPTUNE/spack-stack/source-cache
+  local-binary: file:///p/cwfs/projects/NEPTUNE/spack-stack/build-cache
diff --git a/configs/sites/tier1/nautilus/mirrors.yaml b/configs/sites/tier1/nautilus/mirrors.yaml
index 2b67bea03..5b06fc3fb 100644
--- a/configs/sites/tier1/nautilus/mirrors.yaml
+++ b/configs/sites/tier1/nautilus/mirrors.yaml
@@ -1,18 +1,3 @@
 mirrors:
-  local-source:
-    fetch:
-      url: file:///p/cwfs/projects/NEPTUNE/spack-stack/source-cache
-      access_pair:
-      - null
-      - null
-      access_token: null
-      profile: null
-      endpoint_url: null
-    push:
-      url: file:///p/cwfs/projects/NEPTUNE/spack-stack/source-cache
-      access_pair:
-      - null
-      - null
-      access_token: null
-      profile: null
-      endpoint_url: null
+  local-source: file:///p/cwfs/projects/NEPTUNE/spack-stack/source-cache
+  local-binary: file:///p/cwfs/projects/NEPTUNE/spack-stack/build-cache
diff --git a/doc/source/AutomatedBuilds.rst b/doc/source/AutomatedBuilds.rst
new file mode 100644
index 000000000..18eab61e4
--- /dev/null
+++ b/doc/source/AutomatedBuilds.rst
@@ -0,0 +1,54 @@
+================
+Automated builds
+================
+
+.. _AutomatedBuildWorkflow:
+
+Workflow
+*************************
+
+The spack-stack repository now contains scripts for implementing scheduled, automated building, unit testing, and build caching of packages. These scripts live under utils/weekly_build/. They download their own copy of spack-stack (the develop branch, by default) and build one or more environments under that directory structure, which may be transient or reused.
+
+Script failures are detected by non-zero exit codes.
+
+The list of packages to be unit tested is stored in the ``$PACKAGES_TO_TEST`` variable in ShellSetup.sh. As unit testing needs are identified, this list should be updated to be as comprehensive as possible based on https://github.com/JCSDA/spack-stack/wiki/Automated-testing-and-building#unit-testing-requirements.
+
+.. _AutomatedBuildAddPlatform:
+
+Overview of implementing on a new platform
+******************************************
+
+Use a clean environment. Do NOT run setup.sh in the directory containing the build scripts (util/weekly_build/) to be run. Nothing in spack-stack outside of the build scripts is needed to get the automated build workflow running, as the workflow will take care of download a copy of spack-stack to be used for doing the automated builds themselves.
+
+-------------------------------
+Platform-specific configuration
+-------------------------------
+
+The ShellSetup.sh script points to a script in the sites/ subdirectory based on the site name as set by the third argument of each build script (stored and used as ``$PLATFORM`` throughout the scripts). Note that a number of variables and functions can be set or overridden here:
+ - ``$COMPILERS``: Space-delimited list of compilers to be built against on a given system.
+ - ``$TEMPLATES``: Space-delimited list of templates to install. Default is 'unified-env'.
+ - ``$PACKAGES_TO_TEST``: Space-delimited list of packages for which units tests should be run.
+ - ``$PACKAGES_TO_INSTALL``: Space-delimited list of packages to be installed. For many systems it can be left empty so as to install the entire Unified Environment.
+ - ``alert_cmd()``: This function should be set for each system. It is invoked when any step fails (non-zero exit code somewhere in the workflow), and so can be used to send emails, post to Slack or GitHub, etc.
+ - ``spack_wrapper()``: This function runs the Spack command, where the first argument is a log file name. It should not typically need to be redefined by platform.
+ - ``spack_install_wrapper()``: This function determines the means by which the ``spack`` command is invoked for the install steps, and can be overridden for each platform. If testing and installation will be performed outside of a batch scheduler, i.e., directly on a login node, then the default can probably be used. However, overriding this function allows, for instance, for job schedulers to be invoked (srun, qsub, etc.), as well as for parallel installations to be performed. Note that the first argument is a log file name, so custom versions of this function will most likely need to use ``shift`` to properly access the remaining arguments.
+ - ``$INSTALL_OPTS``: Additional ``spack install`` flags to be supplied to ``spack_install_wrapper()``.
+ - ``$TEST_<APPNAME>``: Set this variable to ON in order to enable the corresponding test under util/weekly_build/apptests/.
+ - ``$BUILD_CACHE``: Name of or path to (beginning with '\file://') build cache directory. Defaults to 'local-binary' mirror defined in site's mirrors.yaml.
+ - ``$SOURCE_CACHE``: Name of or path to (beginning with '\file://') source cache directory. Defaults to 'local-source' mirror defined in site's mirrors.yaml.
+ - ``$PADDED_LENGTH``: Padded length setting for Spack build cache generation. It should be as long as possible without the build failing.
+ - ``$KEEP_WEEKLY_BUILD_DIR``: Set to 'YES' to use a persistent directory structure for automated builds.
+
+------------------------------
+Setting up weekly builds: cron
+------------------------------
+
+Prior to running, obtain a current copy of the build scripts by cloning the spack-stack repository to the platform of interest (/path/to/spack-stack-auto-build/).
+
+If /path/to/spack-stack is the local spack-stack root directory containing spack-stack-x.y.z installations, run ``mkdir -p /path/to/spack-stack/weekly_build/logs``.
+
+In crontab, add:
+
+.. code-block:: console
+
+   0 1 * * SUN /path/to/spack-stack-auto-build/util/weekly_build/SpackStackBuildCache_AllSteps.sh $(date +\%y\%m\%d) /path/to/spack-stack/weekly_build acorn > /path/to/spack-stack/weekly_build/logs/cron.$(date +\%y\%m\%d).out 2>&1
diff --git a/doc/source/index.rst b/doc/source/index.rst
index e084a1ed1..7a67d65f2 100644
--- a/doc/source/index.rst
+++ b/doc/source/index.rst
@@ -19,6 +19,7 @@ Table of contents
    Utilities
    KnownIssues
    MaintainersSection
+   AutomatedBuilds
    Documentation
    Acronyms
    Glossary
diff --git a/util/weekly_build/01_DirectorySetup.sh b/util/weekly_build/01_DirectorySetup.sh
new file mode 100755
index 000000000..f7a2af74a
--- /dev/null
+++ b/util/weekly_build/01_DirectorySetup.sh
@@ -0,0 +1,9 @@
+#!/bin/bash
+
+if [ -z $SETUPDONE ]; then . ShellSetup.sh $* ; fi
+
+set -ex
+
+echo Base directory: ${RUNDIR:?}
+
+mkdir -p $RUNDIR
diff --git a/util/weekly_build/02_GetSpackStack.sh b/util/weekly_build/02_GetSpackStack.sh
new file mode 100755
index 000000000..f1eab34eb
--- /dev/null
+++ b/util/weekly_build/02_GetSpackStack.sh
@@ -0,0 +1,13 @@
+#!/bin/bash
+
+if [ -z $SETUPDONE ]; then . ShellSetup.sh $* ; fi
+
+set -ex
+
+cd $RUNDIR
+if [ -d $RUNID ]; then
+  cd $RUNID
+  git pull
+else
+  git clone --depth 1 --recurse-submodules --shallow-submodules ${SPACK_STACK_URL:-https://github.com/JCSDA/spack-stack} -b ${SPACK_STACK_BRANCH:-develop} $RUNID
+fi
diff --git a/util/weekly_build/03_SetupEnv.sh b/util/weekly_build/03_SetupEnv.sh
new file mode 100755
index 000000000..a98fa6cdd
--- /dev/null
+++ b/util/weekly_build/03_SetupEnv.sh
@@ -0,0 +1,29 @@
+#!/bin/bash
+
+if [ -z $SETUPDONE ]; then . ShellSetup.sh $* ; fi
+
+set -ex
+
+cd $RUNDIR/$RUNID
+
+set +x
+. setup.sh
+set -x
+
+for compiler in $COMPILERS; do
+  for template in $TEMPLATES; do
+    envname=build-$template-${compiler/@/-}
+    envdir=$RUNDIR/$RUNID/envs/$envname
+    echo "Setting up environment $envname in $envdir"
+    rm -rf $envdir
+    spack stack create env --name build-${template}-${compiler/@/-} --template $template --site $PLATFORM --compiler $compiler
+    cd $envdir
+    spack env activate .
+    spack config add "config:install_tree:padded_length:${PADDED_LENGTH:-200}"
+    # Check for duplicates and fail before doing the "real" concretization:
+    spack_wrapper log.concretize concretize --fresh
+    ${SPACK_STACK_DIR:?}/util/show_duplicate_packages.py log.concretize -d -i crtm -i esmf
+#   The following is not working at the moment, for seemingly a couple reasons. Therefore packages with test-only deps cannot be tested.
+#    spack concretize --force --fresh --test all | tee log.concretize_test
+  done
+done
diff --git a/util/weekly_build/04_SpackInstall.sh b/util/weekly_build/04_SpackInstall.sh
new file mode 100755
index 000000000..bddf21f42
--- /dev/null
+++ b/util/weekly_build/04_SpackInstall.sh
@@ -0,0 +1,44 @@
+#!/bin/bash
+
+set -ex
+
+if [ -z $SETUPDONE ]; then . ShellSetup.sh $* ; fi
+
+cd $RUNDIR/${RUNID}
+
+set +x
+. setup.sh
+set -x
+
+if [ "$REUSE_BUILD_CACHE" == YES ]; then
+  cache_flag="--no-check-signature"
+else
+  cache_flag="--no-cache"
+fi
+
+INSTALL_OPTS="--show-log-on-error --fail-fast $cache_flag $INSTALL_OPTS"
+
+for compiler in $COMPILERS; do
+  for template in $TEMPLATES; do
+    envname=build-$template-${compiler/@/-}
+    envdir=$RUNDIR/$RUNID/envs/$envname
+    echo "Building environment $envname in $envdir"
+    cd $envdir
+    spack env activate .
+    if [ "${SOURCE_CACHE::7}" == "file://" ]; then
+      mirrorpath=${SOURCE_CACHE}
+    else
+      mirrorpath=$(spack mirror list | awk "{if (\$1==\"$SOURCE_CACHE\") print \$NF}")
+    fi
+    mirrorpath=${mirrorpath#file://}
+    spack_wrapper log.fetch mirror create --dependencies \
+        --directory ${mirrorpath?"Source mirror path could not be determined. Check site's mirrors.yaml."} \
+        ${PACKAGES_TO_INSTALL:---all}
+    # Just install the packages we're testing (+dependencies):
+    if [[ ! -z "${PACKAGES_TO_TEST}" ]]; then
+      spack_install_wrapper log.install-and-test install $INSTALL_OPTS --test root $PACKAGES_TO_TEST
+    fi
+    # Install the rest of the stack as usual:
+    spack_install_wrapper log.install install $INSTALL_OPTS $PACKAGES_TO_INSTALL
+  done
+done
diff --git a/util/weekly_build/05_BuildCache.sh b/util/weekly_build/05_BuildCache.sh
new file mode 100755
index 000000000..2799c0464
--- /dev/null
+++ b/util/weekly_build/05_BuildCache.sh
@@ -0,0 +1,22 @@
+#!/bin/bash
+
+set -ex
+
+if [ -z $SETUPDONE ]; then . ShellSetup.sh $* ; fi
+
+cd $RUNDIR/$RUNID
+
+set +x
+. setup.sh
+set -x
+
+for compiler in $COMPILERS; do
+  for template in $TEMPLATES; do
+    envname=build-$template-${compiler/@/-}
+    envdir=$RUNDIR/$RUNID/envs/$envname
+    cd $envdir
+    spack env activate .
+    spack buildcache push --unsigned --force ${BUILD_CACHE} $PACKAGES_TO_INSTALL
+    spack buildcache rebuild-index ${BUILD_CACHE}
+  done
+done
diff --git a/util/weekly_build/06_AppTests.sh b/util/weekly_build/06_AppTests.sh
new file mode 100755
index 000000000..a8ee6ffb1
--- /dev/null
+++ b/util/weekly_build/06_AppTests.sh
@@ -0,0 +1,26 @@
+#!/bin/bash
+
+set -ex
+
+if [ -z $SETUPDONE ]; then . ShellSetup.sh $* ; fi
+
+cd $RUNDIR/$RUNID
+
+set +x
+. setup.sh
+set -x
+
+for compiler in $COMPILERS; do
+  for template in $TEMPLATES; do
+    envname=build-$template-${compiler/@/-}
+    envdir=$RUNDIR/$RUNID/envs/$envname
+    cd $envdir
+    spack env activate .
+    spack module lmod refresh -y
+    spack stack setup-meta-modules
+  done
+done
+
+if [ "$TEST_UFSWM" == ON ]; then
+  . $(dirname $0)/apptests/test_ufswm.sh
+fi
diff --git a/util/weekly_build/07_Cleanup.sh b/util/weekly_build/07_Cleanup.sh
new file mode 100755
index 000000000..2d7a1f84e
--- /dev/null
+++ b/util/weekly_build/07_Cleanup.sh
@@ -0,0 +1,9 @@
+#!/bin/bash
+
+set -ex
+
+if [ -z $SETUPDONE ]; then . ShellSetup.sh $* ; fi
+
+if [ "$KEEP_WEEKLY_BUILD_DIR" != YES ]; then
+  /usr/bin/rm -rf ${RUNDIR:?}/${RUNID:?}
+fi
diff --git a/util/weekly_build/README b/util/weekly_build/README
new file mode 100644
index 000000000..31232331b
--- /dev/null
+++ b/util/weekly_build/README
@@ -0,0 +1 @@
+Concretization for deployments should be done with `spack concretize --fresh` so as to ensure that the stack would concretize the same way if the build cache weren't there.
diff --git a/util/weekly_build/ShellSetup.sh b/util/weekly_build/ShellSetup.sh
new file mode 100644
index 000000000..c516e6fb3
--- /dev/null
+++ b/util/weekly_build/ShellSetup.sh
@@ -0,0 +1,42 @@
+echo Run ID: ${1?"First arg: Unique run ID"}
+echo Run directory: ${2?"Second arg: base directory for build"}
+echo Platform name: ${3?"Third arg: platform name ('hera', 'hercules', etc.)"}
+
+RUNID=$1
+RUNDIR=$2
+PLATFORM=$3
+
+if [ ${RUNDIR::1} != "/" ]; then
+  echo "FATAL ERROR: Directory should be an absolute path!"
+  exit 1
+fi
+
+# Defaults to empty, can be overwritten in site config
+PACKAGES_TO_TEST=""
+
+function alert_cmd {
+  echo "Your run failed in $1. This is a placeholder alerting function. 'alert_cmd' should be defined for each system."
+}
+
+function spack_wrapper {
+  logfile=$1
+  shift
+  set -o pipefail
+  spack $* 2>&1 | tee -a $logfile
+}
+
+function spack_install_wrapper {
+  logfile=$1
+  shift
+  set -o pipefail
+  spack $* 2>&1 | tee -a $logfile
+}
+
+# Include platform-dependent configuration
+. $(dirname $0)/sites/${PLATFORM}.sh
+
+SOURCE_CACHE=${SOURCE_CACHE:-local-source}
+BUILD_CACHE=${BUILD_CACHE:-local-binary}
+
+echo "Source cache mirror name/directory: ${SOURCE_CACHE}"
+echo "Build cache mirror name/directory: ${BUILD_CACHE}"
diff --git a/util/weekly_build/SpackStackBuildCache_AllSteps.sh b/util/weekly_build/SpackStackBuildCache_AllSteps.sh
new file mode 100755
index 000000000..73a7931c4
--- /dev/null
+++ b/util/weekly_build/SpackStackBuildCache_AllSteps.sh
@@ -0,0 +1,25 @@
+#!/bin/bash
+
+echo "build host: $(hostname)"
+
+set -exa
+
+cd $(dirname $0)
+
+. ShellSetup.sh $*
+export SETUPDONE=YES
+
+function trap_and_run {
+  trap ERROR ERR
+  scriptname=$1
+  function ERROR { alert_cmd $scriptname ; exit 1;}
+  $*
+}
+
+trap_and_run ./01_DirectorySetup.sh $*
+trap_and_run ./02_GetSpackStack.sh $*
+trap_and_run ./03_SetupEnv.sh $*
+trap_and_run ./04_SpackInstall.sh $*
+trap_and_run ./05_BuildCache.sh $*
+trap_and_run ./06_AppTests.sh $*
+trap_and_run ./07_Cleanup.sh $*
diff --git a/util/weekly_build/apptests/test_ufswm.sh b/util/weekly_build/apptests/test_ufswm.sh
new file mode 100755
index 000000000..030135295
--- /dev/null
+++ b/util/weekly_build/apptests/test_ufswm.sh
@@ -0,0 +1,21 @@
+#!/bin/bash
+
+# Do some stuff, and exit non-zero if UFSWM cannot be successfully built and
+# tested (ideally, have a discernably different error condition if there are
+# numerical differences)
+
+echo "Current directory, in which ufs-weather-model will be cloned: $PWD"
+
+UFSWM_BRANCH=${UFSWM_BRANCH:-develop}
+UFSWM_URL=${UFSWM_URL:-"https://github.com/ufs-community/ufs-weather-model.git"}
+
+if [ ! -d ufs-weather-model ]; then
+  git clone --recurse-submodules --single-branch --depth 1 --shallow-submodules ${UFSWM_URL} -b ${UFSWM_BRANCH}
+fi
+cd ufs-weather-model/tests
+
+# rt.sh will parse arguments passed to it
+./rt.sh $RT_ARGS -a ${BATCHACCOUNT:?} -n 'control_c48 intel'
+
+rc = $?
+return rc
diff --git a/util/weekly_build/sites/acorn.sh b/util/weekly_build/sites/acorn.sh
new file mode 100644
index 000000000..45420c7cf
--- /dev/null
+++ b/util/weekly_build/sites/acorn.sh
@@ -0,0 +1,29 @@
+module load gcc/11.2.0 python/3.11.7
+COMPILERS=${COMPILERS:-"intel@2022.0.2.262 intel@19.1.3.304"}
+TEMPLATES=${TEMPLATES:-"unified-dev"}
+function spack_install_wrapper {
+  logfile=$1
+  shift
+#  set +e
+#  ( /opt/pbs/bin/qsub -N spack-build-cache-$RUNID-A -j oe -A NCEPLIBS-DEV -l select=1:ncpus=6:mem=10000MB -l walltime=03:00:00 -V -Wblock=true -- $(which spack) $* ) &
+#  ( /opt/pbs/bin/qsub -N spack-build-cache-$RUNID-B -j oe -A NCEPLIBS-DEV -l select=1:ncpus=6:mem=10000MB -l walltime=03:00:00 -V -Wblock=true -- $(which spack) $* ) &
+#  wait
+#  rc=$?
+#  set -e
+#  cat spack-build-cache-${RUNID}*
+#  return $rc
+##  cp ${SPACK_STACK_DIR:?}/util/acorn/{build.pbs,spackinstall.sh} ${SPACK_ENV}/.
+##  /opt/pbs/bin/qsub -Wblock=true ${SPACK_ENV}/build.pbs
+##  spack $* | tee -a log.install 2>&1
+  shift 1
+  ${SPACK_STACK_DIR}/util/parallel_install.sh 3 4 $*
+}
+function alert_cmd {
+  module purge # annoying libstdc++ issue
+  mail -s 'spack-stack weekly build failure' alexander.richert@noaa.gov  < <(echo "Weekly spack-stack build failed in $1. Run ID: $RUNID")
+}
+PACKAGES_TO_TEST="libpng libaec jasper w3emc g2c"
+PACKAGES_TO_INSTALL="ufs-weather-model-env global-workflow-env gsi-env madis"
+PADDED_LENGTH=140
+TEST_UFSWM=ON
+BATCHACCOUNT=NCEPLIBS-DEV
diff --git a/util/weekly_build/sites/nautilus.sh b/util/weekly_build/sites/nautilus.sh
new file mode 100644
index 000000000..3c411475a
--- /dev/null
+++ b/util/weekly_build/sites/nautilus.sh
@@ -0,0 +1,10 @@
+COMPILERS=${COMPILERS:-"intel oneapi gcc"}
+#TEMPLATES=${TEMPLATES:-"neptune-dev unified-dev"}
+TEMPLATES=${TEMPLATES:-"neptune-dev"}
+module purge
+umask 0022
+
+SPACK_STACK_URL=https://github.nrlmry.navy.mil/JCSDA/spack-stack
+SPACK_STACK_BRANCH=feature/weekly_build_nautilus
+KEEP_WEEKLY_BUILD_DIR="YES"
+
diff --git a/util/weekly_build/sites/orion.sh b/util/weekly_build/sites/orion.sh
new file mode 100644
index 000000000..9f202a9f5
--- /dev/null
+++ b/util/weekly_build/sites/orion.sh
@@ -0,0 +1,28 @@
+
+COMPILERS=${COMPILERS:-"intel"}
+TEMPLATES=${TEMPLATES:-"unified-dev"}
+
+function alert_cmd {
+  mail -s 'spack-stack weekly build failure' richard.grubin@noaa.gov < <(echo "Weekly spack-stack build failed in $1. Run ID: $RUNID")
+}
+
+module --force purge
+umask 0022
+
+SPACK_STACK_URL=https://github.com/JCSDA/spack-stack.git
+SPACK_STACK_BRANCH=develop
+
+KEEP_WEEKLY_BUILD_DIR="YES"
+PADDED_LENGTH=200
+
+# package test / install settings (future use)
+# PACKAGES_TO_TEST="libpng libaec jasper w3emc g2c"
+# PACKAGES_TO_INSTALL="ufs-weather-model-env"
+
+TEST_UFSWM=ON
+UFSWM_BRANCH=develop
+UFSWM_URL="https://github.com/ufs-community/ufs-weather-model.git"
+
+# rt.sh parameters / arguments
+BATCHACCOUNT=epic
+RT_ARGS="-k -r"