diff --git a/action.yml b/action.yml
index 9cd2164..ee46a33 100644
--- a/action.yml
+++ b/action.yml
@@ -57,6 +57,7 @@ runs:
           / \
           "${{ steps.load-cache.outputs.cache-hit }}" \
           ${{ inputs.packages }}
-        echo "::set-output name=package-version-list::$(cat ~/cache-apt-pkgs/manifest_main.log)"
-        echo "::set-output name=all-package-version-list::$(cat ~/cache-apt-pkgs/manifest_all.log)"
+        function create_list { local list=$(cat ~/cache-apt-pkgs/manifest_${1}.log | tr '\n' ','); echo ${list:0:-1}; };
+        echo "::set-output name=package-version-list::$(create_list main)"
+        echo "::set-output name=all-package-version-list::$(create_list all)"
       shell: bash
diff --git a/install_and_cache_pkgs.sh b/install_and_cache_pkgs.sh
index 1d420b2..1049d9b 100755
--- a/install_and_cache_pkgs.sh
+++ b/install_and_cache_pkgs.sh
@@ -75,14 +75,5 @@ for package in ${normalized_packages}; do
 done
 log "done."
 
-manifest_all_filepath="${cache_dir}/manifest_all.log"
-log "Writing all packages manifest to ${manifest_all_filepath}..."
-# Remove trailing comma and write to manifest_all file.
-echo "${manifest_all:0:-1}" > "${manifest_all_filepath}"
-log "done."
-
-manifest_main_filepath="${cache_dir}/manifest_main.log"
-log "Writing main requested packages manifest to ${manifest_main_filepath}..."
-# Remove trailing comma and write to manifest_main file.
-echo "${manifest_main:0:-1}" > "${manifest_main_filepath}"
-log "done."
+write_manifest "all" "${manifest_all}" "${cache_dir}/manifest_all.log"
+write_manifest "main" "${manifest_main}" "${cache_dir}/manifest_main.log"
diff --git a/lib.sh b/lib.sh
index fc8eb1e..74255ca 100755
--- a/lib.sh
+++ b/lib.sh
@@ -27,4 +27,11 @@ function get_package_name_ver {
   echo "${name}" "${ver}"
 }
 
-function log { echo "$(date +%H:%M:%S)" "${@}"; }
\ No newline at end of file
+function log { echo "$(date +%H:%M:%S)" "${@}"; }
+
+function write_manifest {  
+  log "Writing ${1} packages manifest to ${3}..."  
+  # 0:-1 to remove trailing comma, delimit by newline and sort
+  echo "${2:0:-1}" | tr ',' '\n' | sort > ${3}
+  log "done."
+}
\ No newline at end of file