diff --git a/Makefile b/Makefile
index de7093a..75c0cc2 100644
--- a/Makefile
+++ b/Makefile
@@ -95,4 +95,6 @@
 clean :: ## clean the build environment
 	$(RM) -r local_imports
 
+sterile :: clean
+
 # end file
diff --git a/VERSION b/VERSION
index d4bda08..fc3aa77 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-5.1.8
+5.1.9
diff --git a/app-install.sh b/app-install.sh
index b810097..b783565 100755
--- a/app-install.sh
+++ b/app-install.sh
@@ -13,22 +13,66 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-HERE=$(pwd)
-OARS=$(find $DOWNLOAD_ROOT -name "*.oar")
-for oar in $OARS; do
-    cd $HERE
+##-------------------##
+##---]  GLOBALS  [---##
+##-------------------##
+# set -euo pipefail
+umask 022
+declare -g HERE; HERE="$(pwd)"
+
+## -----------------------------------------------------------------------
+## Intent: Display an error mesage then exit with shell exit status
+## -----------------------------------------------------------------------
+function error()
+{
+    echo "${BASH_SOURCE[0]} ERROR: $*"
+    exit 1
+}
+
+## -----------------------------------------------------------------------
+## Intent: Verify required environment variables are set
+## -----------------------------------------------------------------------
+function init()
+{
+    [[ ! -v APP_INSTALL_ROOT ]] && error "Var APP_INSTALL_ROOT= is required"
+    [[ ! -v DOWNLOAD_ROOT ]]    && error "Var DOWNLOAD_ROOT= is required"
+    return
+}
+
+##----------------##
+##---]  MAIN  [---##
+##----------------##
+
+init
+
+readarray -t OARS < <(find "$DOWNLOAD_ROOT" -name '*.oar')
+for oar in "${OARS[@]}"; do
+
+    app_xml="$APP_INSTALL_ROOT/app.xml"
+    oar_basename="${oar##*/}"    # bash builtin
+
+    cd "$HERE" || error "cd $HERE failed"
     echo "Installing application '$oar'"
-    rm -rf $APP_INSTALL_ROOT
-    mkdir -p $APP_INSTALL_ROOT
-    cd $APP_INSTALL_ROOT
-    cp $oar $APP_INSTALL_ROOT
-    unzip -oq -d . $APP_INSTALL_ROOT/$(basename $oar)
-    name=$(grep "name=" $APP_INSTALL_ROOT/app.xml | sed 's/<app name="//g;s/".*//g')
-    mkdir -p $APPS_ROOT/$name
-    cp $APP_INSTALL_ROOT/app.xml $APPS_ROOT/$name/app.xml
-    touch $APPS_ROOT/$name/active
-    [ -f $APP_INSTALL_ROOT/app.png ] && cp $APP_INSTALL_ROOT/app.png $APPS_ROOT/$name/app.png
-    cp $APP_INSTALL_ROOT/$(basename $oar) $APPS_ROOT/$name/$name.oar
-    cp -rf $APP_INSTALL_ROOT/m2/* $KARAF_M2
-    rm -rf $APP_INSTALL_ROOT
+    rm -rf "$APP_INSTALL_ROOT"
+    mkdir -p "$APP_INSTALL_ROOT"
+    cd "$APP_INSTALL_ROOT"  || error "cd $APP_INSTALL_ROOT failed"
+    cp -v "$oar" "$APP_INSTALL_ROOT"
+    unzip -oq -d . "$APP_INSTALL_ROOT/${oar_basename}"
+
+    readarray -t names < <(grep "name=" "$app_xml" \
+			       | sed 's/<app name="//g;s/".*//g')
+    [[ ${#names[@]} -gt 0 ]] || error "Detected invalid name gathering"
+    name="${names[1]}"
+    apps_name="$APPS_ROOT/$name"
+
+    mkdir -p "$apps_name"
+    cp "$app_xml" "${apps_name}/app.xml"
+    touch "${apps_name}/active"
+    [ -f "$APP_INSTALL_ROOT/app.png" ] \
+	&& cp "$APP_INSTALL_ROOT/app.png" "${apps_name}/app.png"
+    cp "${APP_INSTALL_ROOT}/${oar_basename}" "${apps_name}/${name}.oar"
+    cp -rf "$APP_INSTALL_ROOT/m2/"* "$KARAF_M2"
+    rm -rf "$APP_INSTALL_ROOT"
 done
+
+# [EOF]
diff --git a/makefiles/virtualenv/include.mk b/makefiles/virtualenv/include.mk
index 9ae62a4..4dd2aa1 100644
--- a/makefiles/virtualenv/include.mk
+++ b/makefiles/virtualenv/include.mk
@@ -1,6 +1,6 @@
 # -*- makefile -*-
 ## -----------------------------------------------------------------------
-# Copyright 2017-2023 Open Networking Foundation (ONF) and the ONF Contributors
+# Copyright 2017-2024 Open Networking Foundation (ONF) and the ONF Contributors
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/makefiles/virtualenv/python_310_migration.sh b/makefiles/virtualenv/python_310_migration.sh
index c666f59..5155768 100644
--- a/makefiles/virtualenv/python_310_migration.sh
+++ b/makefiles/virtualenv/python_310_migration.sh
@@ -1,6 +1,6 @@
 #!/bin/bash
 # -----------------------------------------------------------------------
-# Copyright 2022-2023 Open Networking Foundation (ONF) and the ONF Contributors
+# Copyright 2022-2024 Open Networking Foundation (ONF) and the ONF Contributors
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/tests/version-check.sh b/tests/version-check.sh
index 0d76faf..e1fb354 100644
--- a/tests/version-check.sh
+++ b/tests/version-check.sh
@@ -1,5 +1,5 @@
+#!/bin/bash
 # Copyright 2021-2024 Open Networking Foundation (ONF) and the ONF Contributors
-
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
@@ -12,16 +12,27 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-CWD=$( dirname ${BASH_SOURCE[0]} )
-NEW_VERSION=$(head -n1 "$CWD/../VERSION")
+set -euo pipefail
+
+pgm_dir="${BASH_SOURCE[0]%/*}"
+cd "$pgm_dir/.."
+
+NEW_VERSION="$(head -n1 'VERSION')"
 
 if [[ "$NEW_VERSION" =~ ^([0-9]+)\.([0-9]+)\.([0-9]+)$ ]]
 then
   echo "Version string '$NEW_VERSION' is a SemVer released version!"
-  SNAPSHOTS=$(cat "$CWD/../dependencies.xml" | grep "SNAPSHOT" | wc -l)
-  if [[ "$SNAPSHOTS" -gt 0 ]]
+  declare -i SNAPSHOTS
+  SNAPSHOTS=$(grep --count "SNAPSHOT" 'dependencies.xml')
+  if [[ $SNAPSHOTS -gt 0 ]]
   then
     echo "ERROR: Referring to -SNAPSHOT apps in a released VERSION"
     exit 1
   fi
+
+elif [[ "$NEW_VERSION" =~ '-dev' ]]; then
+    echo "** Developement version detected: $(declare -p NEW_VERSION)"
+
+else
+    echo "** Detected odd version string: $(declare -p NEW_VERSION)"
 fi