diff --git a/action.yml b/action.yml
index 38d4e13..e717de5 100644
--- a/action.yml
+++ b/action.yml
@@ -25,9 +25,6 @@ outputs:
     # This compound expression is needed because lhs can be empty.
     # Need to output true and false instead of true and nothing.
     value: ${{ steps.load-cache.outputs.cache-hit || false }}
-  cache-key:
-    description: 'The key where the cache is stored with packages, their versions, and the cache version (i.e. package=version package=version @ 1).'
-    value: ${{ steps.pre-cache.outputs.cache-key }}
   package-version-list:
     description: 'The packages and versions that are installed as a comma delimited list with colon delimit on the package version (i.e. <package>:<version,<package>:<version>).'
     value: ${{ steps.post-cache.outputs.package-version-list }}
@@ -42,7 +39,6 @@ runs:
           "${{ inputs.version }}" \
           ${{ inputs.packages }}
         echo "CACHE_KEY=$(cat ~/cache-apt-pkgs/cache_key.md5)" >> $GITHUB_ENV
-        echo "::set-output name=cache-key::$(cat ~/cache-apt-pkgs/cache_key.md5)"
       shell: bash
 
     - id: load-cache
diff --git a/install_and_cache_pkgs.sh b/install_and_cache_pkgs.sh
index 337628f..e4f6c2c 100755
--- a/install_and_cache_pkgs.sh
+++ b/install_and_cache_pkgs.sh
@@ -8,7 +8,7 @@ script_dir="$(dirname -- "$(realpath -- "${0}")")"
 source "${script_dir}/lib.sh"
 
 # Directory that holds the cached packages.
-cache_dir="${1}"
+cache_dir=$1
 
 # List of the packages to use.
 input_packages="${@:2}"
@@ -27,7 +27,7 @@ echo -n "Updating APT package list..."
 sudo apt-get update > /dev/null
 echo "done."
 
-manifest=
+manifest=""
 echo "Clean installing and caching ${package_count} packages..."
 for package in "${packages}"; do
   get_package_name_ver "${package}" # -> package_name, package_ver
diff --git a/post_cache_action.sh b/post_cache_action.sh
index 0bb091f..5503013 100755
--- a/post_cache_action.sh
+++ b/post_cache_action.sh
@@ -4,23 +4,23 @@
 set -e
 
 # Directory that holds the cached packages.
-cache_dir="${1}"
+cache_dir=$1
 
 # Root directory to untar the cached packages to.
 # Typically filesystem root '/' but can be changed for testing.
-cache_restore_root="${2}"
+cache_restore_root=$2
 
 # Indicates that the cache was found.
-cache_hit="${3}"
+cache_hit=$3
 
 # List of the packages to use.
 packages="${@:4}"
 
-script_dir="$(dirname -- "$(realpath -- "${0}")")"
+script_dir=$(dirname $0)
 
-if [ "${cache_hit}" == true ]; then
-  "${script_dir}/restore_pkgs.sh" ~/cache-apt-pkgs "${cache_restore_root}"
+if [ "$cache_hit" == true ]; then
+  $script_dir/restore_pkgs.sh ~/cache-apt-pkgs $cache_restore_root
 else
-  "${script_dir}/install_and_cache_pkgs.sh" ~/cache-apt-pkgs "${packages}"
+  $script_dir/install_and_cache_pkgs.sh ~/cache-apt-pkgs $packages
 fi
 echo ""
diff --git a/pre_cache_action.sh b/pre_cache_action.sh
index 8c8f992..7c03802 100755
--- a/pre_cache_action.sh
+++ b/pre_cache_action.sh
@@ -5,10 +5,10 @@ script_dir="$(dirname -- "$(realpath -- "${0}")")"
 source "${script_dir}/lib.sh"
 
 # Directory that holds the cached packages.
-cache_dir="${1}"
+cache_dir=$1
 
 # Version of the cache to create or load.
-cache_version="${2}"
+version=$2
 
 # List of the packages to use.
 input_packages="${@:3}"
@@ -17,15 +17,15 @@ input_packages="${@:3}"
 packages="$(normalize_package_list "${input_packages}")"
 
 # Create cache directory so artifacts can be saved.
-mkdir -p "${cache_dir}"
-
-echo -n "Validating action arguments (version='${cache_version}', packages='${packages}')...";
+mkdir -p $cache_dir
 
+echo -n "Validating action arguments (version='$version', packages='$packages')...";
 if grep -q " " <<< "${cache_version}"; then
   echo "aborted." 
-  echo "Version value '${cache_version}' cannot contain spaces." >&2
+  echo "Version value '$version' cannot contain spaces." >&2
   exit 1
 fi
+
 # Is length of string zero?
 if test -z "${packages}"; then
   echo "aborted." 
@@ -34,16 +34,12 @@ if test -z "${packages}"; then
 fi
 echo "done."
 
-echo -n "Updating APT package list..."
-sudo apt-get update > /dev/null
-echo "done."
-
 versioned_packages=""
 echo -n "Verifying packages..."
 for package in ${packages}; do 
   if test ! "$(apt show "${package}")"; then
     echo "aborted."
-    echo "Package '${package}' not found." >&2
+    echo "Package '$package' not found." >&2
     exit 3
   fi
   get_package_name_ver "${package}" # -> package_name, package_ver  
@@ -68,6 +64,6 @@ echo "- Value hashed as '${key}'."
 
 echo "done."
 
-key_filepath="${cache_dir}/cache_key.md5"
-echo "${key}" > "${key_filepath}"
-echo "Hash value written to ${key_filepath}"
+key_filepath="$cache_dir/cache_key.md5"
+echo $key > $key_filepath
+echo "Hash value written to $key_filepath"
diff --git a/restore_pkgs.sh b/restore_pkgs.sh
index 87ee131..4c710f3 100755
--- a/restore_pkgs.sh
+++ b/restore_pkgs.sh
@@ -4,16 +4,16 @@
 set -e
 
 # Directory that holds the cached packages.
-cache_dir="${1}"
+cache_dir=$1
 
 # Root directory to untar the cached packages to.
 # Typically filesystem root '/' but can be changed for testing.
-cache_restore_root="${2}"
+cache_restore_root=$2
 
-cache_filepaths="$(ls -1 "${cache_dir}" | sort)"
-echo "Found $(echo "${cache_filepaths}" | wc -w) files in the cache."
-for cache_filepath in ${cache_filepaths}; do
-  echo "- $(basename "${cache_filepath}")"
+cache_filepaths=$(ls -1 $cache_dir | sort)
+echo "Found $(echo $cache_filepaths | wc -w) files in the cache."
+for cache_filepath in $cache_filepaths; do
+  echo "- $(basename $cache_filepath)"
 done
 
 echo "Reading from manifest..."
@@ -23,12 +23,12 @@ done
 echo "done."
 
 # Only search for archived results. Manifest and cache key also live here.
-cache_pkg_filepaths=$(ls -1 ${cache_dir}/*.tar.gz | sort)
-cache_pkg_filecount=$(echo "${cache_pkg_filepaths}" | wc -w)
-echo "Restoring ${cache_pkg_filecount} packages from cache..."
-for cache_pkg_filepath in ${cache_pkg_filepaths}; do
-  echo -n "- $(basename "${cache_pkg_filepath}") restoring..."
-  sudo tar -xf ${cache_pkg_filepath} -C ${cache_restore_root} > /dev/null
+cache_pkg_filepaths=$(ls -1 $cache_dir/*.tar.gz | sort)
+cache_pkg_filecount=$(echo $cache_pkg_filepaths | wc -w)
+echo "Restoring $cache_pkg_filecount packages from cache..."
+for cache_pkg_filepath in $cache_pkg_filepaths; do
+  echo -n "- $(basename $cache_pkg_filepath) restoring..."
+  sudo tar -xf $cache_pkg_filepath -C $cache_restore_root > /dev/null
   echo "done."
 done
 echo "done."