diff --git a/lib.sh b/lib.sh
index fd7764d..daa554e 100755
--- a/lib.sh
+++ b/lib.sh
@@ -99,57 +99,11 @@ function get_normalized_package_list {
   # Remove commas, and block scalar folded backslashes,
   # extraneous spaces at the middle, beginning and end
   # then sort.
-  packages=$(echo "${1}" \
+  local packages=$(echo "${1}" \
     | sed 's/[,\]/ /g; s/\s\+/ /g; s/^\s\+//g; s/\s\+$//g' \
     | sort -t' ')
-
-  # Validate package names and get versions.
-  log_err "resolving package versions..."
-  data=$(apt-cache --quiet=0 --no-all-versions show ${packages} 2>&1 | \
-    grep -E '^(Package|Version|N):')
-  log_err "resolved"
-
-  local ORIG_IFS="${IFS}"
-  IFS=$'\n'
-  declare -A missing
-  local package_versions=''
-  local package='' separator=''
-  for key_value in ${data}; do
-    local key="${key_value%%: *}"
-    local value="${key_value##*: }"
-
-    case $key in
-      Package)
-        package=$value
-        ;;
-      Version)
-        package_versions="${package_versions}${separator}"${package}=${value}""
-        separator=' '
-        ;;
-      N)
-        # Warning messages.
-        case $value in
-          'Unable to locate package '*)
-            package="${value#'Unable to locate package '}"
-            # Avoid duplicate messages.
-            if [ -z "${missing[$package]}" ]; then
-              package="${value#'Unable to locate package '}"
-              log_err "Package '${package}' not found."
-              missing[$package]=1
-            fi
-            ;;
-        esac
-        ;;
-    esac
-  done
-  IFS="${ORIG_IFS}"
-
-  if [ ${#missing[@]} -gt 0 ]; then
-    echo "aborted"
-    exit 5
-  fi
-
-  echo "${package_versions}"
+  local script_dir="$(dirname -- "$(realpath -- "${0}")")"
+  go ${script_dir}/apt_query.go normalized-list ${packages}
 }
 
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