diff --git a/util-iso.sh b/util-iso.sh
index e6e67b0..437f070 100755
--- a/util-iso.sh
+++ b/util-iso.sh
@@ -146,7 +146,7 @@ run_build() {
     sudo chown $USER $outFolder
 
     cp ${work_dir}/iso/arch/pkglist.x86_64.txt "$outFolder/$_profile/$(gen_iso_fn).pkgs.txt"
-    mv "$outFolder/$_profile/cachyos-$(date +%Y.%m.%d)-x86_64.iso" "$outFolder/$_profile/${iso_file}"
+    mv "$outFolder/$_profile/cachyos-$(date --date="@${SOURCE_DATE_EPOCH:-$(date +%s)}" +%Y.%m.%d)-x86_64.iso" "$outFolder/$_profile/${iso_file}"
 
     msg "Done [Build ISO] ${iso_file}"
     msg "Finished building [%s]" "${_profile}"
diff --git a/util.sh b/util.sh
index 046ff81..031d524 100755
--- a/util.sh
+++ b/util.sh
@@ -95,5 +95,10 @@ sign_with_key() {
 
     msg2 "signing [%s] with key %s" "${1##*/}" "${GPGKEY}"
     [[ -e "$1".sig ]] && rm "$1".sig
-    gpg --detach-sign --use-agent -u "${GPGKEY}" "$1"
+
+    local SIGNWITHKEY=()
+    if [[ -n $GPGKEY ]]; then
+        SIGNWITHKEY=(-u "${GPGKEY}")
+    fi
+    gpg --detach-sign --use-agent "${SIGNWITHKEY[@]}" "$1"
 }