diff --git a/scripts/build-dmg.sh b/scripts/build-dmg.sh
new file mode 100755
index 0000000..386727c
--- /dev/null
+++ b/scripts/build-dmg.sh
@@ -0,0 +1,129 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+PROJECT_DIR="$ROOT_DIR/CommandNotch"
+PROJECT_SPEC="$PROJECT_DIR/project.yml"
+XCODEPROJ="$PROJECT_DIR/CommandNotch.xcodeproj"
+SCHEME="Release-CommandNotch"
+CONFIGURATION="Release"
+APP_NAME="CommandNotch"
+DERIVED_DATA_DIR="$ROOT_DIR/build/release"
+DIST_DIR="$ROOT_DIR/dist"
+STAGING_DIR="$DIST_DIR/dmg"
+APP_BUNDLE="$DERIVED_DATA_DIR/Build/Products/$CONFIGURATION/$APP_NAME.app"
+DMG_PATH="$DIST_DIR/$APP_NAME.dmg"
+
+usage() {
+  cat <<EOF
+Usage: $(basename "$0") [--skip-generate]
+
+Builds $APP_NAME.app and packages it into a drag-to-Applications DMG.
+
+Options:
+  --skip-generate   Reuse the existing Xcode project without running xcodegen.
+  -h, --help        Show this help text.
+EOF
+}
+
+require_command() {
+  if ! command -v "$1" >/dev/null 2>&1; then
+    echo "error: required command not found: $1" >&2
+    exit 1
+  fi
+}
+
+configure_developer_dir() {
+  local current_dir
+  current_dir="$(xcode-select -p 2>/dev/null || true)"
+
+  if [[ "$current_dir" == "/Library/Developer/CommandLineTools" ]]; then
+    local xcode_dir="/Applications/Xcode.app/Contents/Developer"
+    if [[ -d "$xcode_dir" ]]; then
+      export DEVELOPER_DIR="$xcode_dir"
+      echo "Using Xcode developer directory: $DEVELOPER_DIR"
+      return
+    fi
+
+    echo "error: xcode-select is pointing at Command Line Tools, and /Applications/Xcode.app was not found." >&2
+    echo "Install Xcode or run: sudo xcode-select -s /Applications/Xcode.app/Contents/Developer" >&2
+    exit 1
+  fi
+}
+
+skip_generate=0
+
+while (($# > 0)); do
+  case "$1" in
+    --skip-generate)
+      skip_generate=1
+      shift
+      ;;
+    -h|--help)
+      usage
+      exit 0
+      ;;
+    *)
+      echo "error: unknown argument: $1" >&2
+      usage >&2
+      exit 1
+      ;;
+  esac
+done
+
+require_command xcodebuild
+require_command hdiutil
+if [[ $skip_generate -eq 0 ]]; then
+  require_command xcodegen
+fi
+
+configure_developer_dir
+
+if [[ ! -f "$PROJECT_SPEC" ]]; then
+  echo "error: project spec not found at $PROJECT_SPEC" >&2
+  exit 1
+fi
+
+if [[ $skip_generate -eq 0 ]]; then
+  echo "Generating Xcode project..."
+  xcodegen generate --spec "$PROJECT_SPEC"
+fi
+
+if [[ ! -d "$XCODEPROJ" ]]; then
+  echo "error: Xcode project not found at $XCODEPROJ" >&2
+  exit 1
+fi
+
+echo "Building $APP_NAME.app..."
+rm -rf "$DERIVED_DATA_DIR"
+xcodebuild \
+  -project "$XCODEPROJ" \
+  -scheme "$SCHEME" \
+  -configuration "$CONFIGURATION" \
+  -derivedDataPath "$DERIVED_DATA_DIR" \
+  build
+
+if [[ ! -d "$APP_BUNDLE" ]]; then
+  echo "error: built app bundle not found at $APP_BUNDLE" >&2
+  exit 1
+fi
+
+echo "Preparing DMG staging folder..."
+rm -rf "$STAGING_DIR" "$DMG_PATH"
+mkdir -p "$STAGING_DIR"
+ditto "$APP_BUNDLE" "$STAGING_DIR/$APP_NAME.app"
+ln -s /Applications "$STAGING_DIR/Applications"
+
+echo "Creating DMG..."
+hdiutil create \
+  -volname "$APP_NAME" \
+  -srcfolder "$STAGING_DIR" \
+  -ov \
+  -format UDZO \
+  "$DMG_PATH"
+
+echo
+echo "Done:"
+echo "  App: $APP_BUNDLE"
+echo "  DMG: $DMG_PATH"