diff --git a/ios/patching/001-social-app-ios-config.patch b/ios/patching/001-social-app-ios-config.patch
index b16e999..b132480 100644
--- a/ios/patching/001-social-app-ios-config.patch
+++ b/ios/patching/001-social-app-ios-config.patch
@@ -14,7 +14,7 @@ index 246d8abd3..ed8f7b2b2 100644
      // When testing local services, enter an ngrok (et al) domain here. It must use a standard HTTP/HTTPS port.
      ...(IS_DEV || IS_TESTFLIGHT ? [] : []),
    ]
-@@ -33,27 +30,24 @@ module.exports = function (_config) {
+@@ -33,27 +30,25 @@ module.exports = function (_config) {
    return {
      expo: {
        version: VERSION,
@@ -37,6 +37,7 @@ index 246d8abd3..ed8f7b2b2 100644
          supportsTablet: false,
 -        bundleIdentifier: 'xyz.blueskyweb.app',
 +        bundleIdentifier: 'ai.syui.at',
++        buildNumber: '__BUILD_NUMBER__',
          config: {
            usesNonExemptEncryption: false,
          },
diff --git a/ios/setup.zsh b/ios/setup.zsh
index 43a204a..cff4f22 100755
--- a/ios/setup.zsh
+++ b/ios/setup.zsh
@@ -5,6 +5,15 @@ cd ${0:a:h}
 # iOS Social App Patch Setup Script
 # Usage: ./ios/setup.zsh [patch|reset]
 
+# Cross-platform sed (macOS vs Linux)
+function sediment() {
+	if [[ "$OSTYPE" == "darwin"* ]]; then
+		sed -i '' "$@"
+	else
+		sed -i "$@"
+	fi
+}
+
 # Arrays for patch management
 typeset -a FAILED_PATCHES
 
@@ -114,6 +123,30 @@ function patch-apply() {
 	apply-patch "${name}" "$target_dir" "$patching_dir/${patch_file}"
 }
 
+# Generate build number from timestamp (YYMMDDHHMMSS)
+function ios-generate-build-number() {
+	local build_number=$(date +%y%m%d%H%M%S)
+	local config_patch="$patching_dir/001-social-app-ios-config.patch"
+
+	if [ -f "$config_patch" ]; then
+		# Replace placeholder with timestamp
+		sediment "s/__BUILD_NUMBER__/${build_number}/" "$config_patch"
+		echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+		echo "🔢 Build number: ${build_number}"
+		echo ""
+	fi
+}
+
+# Restore placeholder after patching (for git cleanliness)
+function ios-restore-build-placeholder() {
+	local config_patch="$patching_dir/001-social-app-ios-config.patch"
+
+	if [ -f "$config_patch" ]; then
+		# Restore placeholder for next build
+		sediment "s/buildNumber: '[0-9]*'/buildNumber: '__BUILD_NUMBER__'/" "$config_patch"
+	fi
+}
+
 # Auto-apply patches from list
 function ios-patch-apply-all() {
 	for filename in "${PATCH_FILES_IOS[@]}"; do
@@ -166,7 +199,9 @@ ios-env
 case "$1" in
 	patch)
 		ios-setup-clone
+		ios-generate-build-number
 		ios-patch-apply-all
+		ios-restore-build-placeholder
 		ios-copy-new-files
 		show-failed-patches
 		exit
@@ -177,7 +212,9 @@ case "$1" in
 		;;
 	*)
 		ios-setup-clone
+		ios-generate-build-number
 		ios-patch-apply-all
+		ios-restore-build-placeholder
 		ios-copy-new-files
 		show-failed-patches
 		;;