diff --git a/pkgs/by-name/ge/geoserver/update.sh b/pkgs/by-name/ge/geoserver/update.sh
index e3b2f25fbaa4..a172161e1a91 100755
--- a/pkgs/by-name/ge/geoserver/update.sh
+++ b/pkgs/by-name/ge/geoserver/update.sh
@@ -2,7 +2,7 @@
 #!nix-shell -I ./. -i bash -p common-updater-scripts jq
 
 set -eEuo pipefail
-test ${DEBUG:-0} -eq 1 && set -x
+test "${DEBUG:-0}" -eq 1 && set -x
 
 # Current version.
 LATEST_NIXPKGS_VERSION=$(nix eval --raw .#geoserver.version 2>/dev/null)
@@ -12,7 +12,7 @@ UPDATE_NIX_OLD_VERSION=${UPDATE_NIX_OLD_VERSION:-$LATEST_NIXPKGS_VERSION}
 LATEST_GITHUB_VERSION=$(curl -s "https://api.github.com/repos/geoserver/geoserver/releases/latest" | jq -r '.tag_name')
 UPDATE_NIX_NEW_VERSION=${UPDATE_NIX_NEW_VERSION:-$LATEST_GITHUB_VERSION}
 
-SMALLEST_VERSION=$(printf "$UPDATE_NIX_OLD_VERSION\n$UPDATE_NIX_NEW_VERSION" | sort --version-sort | head -n 1)
+SMALLEST_VERSION=$(printf "%s\n%s" "$UPDATE_NIX_OLD_VERSION" "$UPDATE_NIX_NEW_VERSION" | sort --version-sort | head -n 1)
 
 if [[ "$SMALLEST_VERSION" == "$UPDATE_NIX_NEW_VERSION" ]]; then
   echo "geoserver is up-to-date: $SMALLEST_VERSION"
@@ -24,18 +24,18 @@ update-source-version geoserver "$UPDATE_NIX_NEW_VERSION"
 
 cd "$(dirname "$(readlink -f "$0")")"
 
-EXT_NAMES=($(grep -o -E "hash = .*?; # .*$" ./extensions.nix | sed 's/.* # //' | sort))
+mapfile -t EXT_NAMES < <(grep -o -E "hash = .*?; # .*$" ./extensions.nix | sed 's/.* # //' | sort)
 
-if [[ $# -gt 0 ]] ; then
-    EXT_NAMES=(${@:1})
+if [[ $# -gt 0 ]]; then
+  EXT_NAMES=("${@:1}")
 fi
 
-for EXT_NAME in "${EXT_NAMES[@]}" ; do
-    echo "Updating extension $EXT_NAME..."
-    URL="mirror://sourceforge/geoserver/GeoServer/${UPDATE_NIX_NEW_VERSION}/extensions/geoserver-${UPDATE_NIX_NEW_VERSION}-${EXT_NAME}-plugin.zip"
-    HASH=$(nix-hash --to-sri --type sha256 $(nix-prefetch-url --unpack "$URL"))
-    sed -i "s@version = \".*\"; # $EXT_NAME@version = \"$UPDATE_NIX_NEW_VERSION\"; # $EXT_NAME@" ./extensions.nix
-    sed -i "s@hash = \".*\"; # $EXT_NAME@hash = \"$HASH\"; # $EXT_NAME@" ./extensions.nix
+for EXT_NAME in "${EXT_NAMES[@]}"; do
+  echo "Updating extension $EXT_NAME..."
+  URL="mirror://sourceforge/geoserver/GeoServer/${UPDATE_NIX_NEW_VERSION}/extensions/geoserver-${UPDATE_NIX_NEW_VERSION}-${EXT_NAME}-plugin.zip"
+  HASH=$(nix-hash --to-sri --type sha256 "$(nix-prefetch-url --unpack "$URL")")
+  sed -i "s@version = \".*\"; # $EXT_NAME@version = \"$UPDATE_NIX_NEW_VERSION\"; # $EXT_NAME@" ./extensions.nix
+  sed -i "s@hash = \".*\"; # $EXT_NAME@hash = \"$HASH\"; # $EXT_NAME@" ./extensions.nix
 done
 
 cd -