diff --git a/docs/mac/release.md b/docs/mac/release.md
index 0ea3be3ff..7ac225cc7 100644
--- a/docs/mac/release.md
+++ b/docs/mac/release.md
@@ -23,7 +23,7 @@ This app now ships Sparkle auto-updates. Release builds must be Developer ID–s
 ## Build & package
 Notes:
 - `APP_BUILD` maps to `CFBundleVersion`/`sparkle:version`; keep it numeric + monotonic (no `-beta`), or Sparkle compares it as equal.
-- Universal by default (`arm64 x86_64`). Override with `BUILD_ARCHS="arm64"` if you need arm-only.
+- Defaults to the current architecture (`$(uname -m)`). For release/universal builds, set `BUILD_ARCHS="arm64 x86_64"` (or `BUILD_ARCHS=all`).
 
 ```bash
 # From repo root; set release IDs so Sparkle feed is enabled.
diff --git a/scripts/package-mac-app.sh b/scripts/package-mac-app.sh
index 884e1c842..7c7fe1b1f 100755
--- a/scripts/package-mac-app.sh
+++ b/scripts/package-mac-app.sh
@@ -16,7 +16,10 @@ GIT_BUILD_NUMBER=$(cd "$ROOT_DIR" && git rev-list --count HEAD 2>/dev/null || ec
 APP_VERSION="${APP_VERSION:-$PKG_VERSION}"
 APP_BUILD="${APP_BUILD:-$GIT_BUILD_NUMBER}"
 BUILD_CONFIG="${BUILD_CONFIG:-debug}"
-BUILD_ARCHS_VALUE="${BUILD_ARCHS:-arm64 x86_64}"
+BUILD_ARCHS_VALUE="${BUILD_ARCHS:-$(uname -m)}"
+if [[ "${BUILD_ARCHS_VALUE}" == "all" ]]; then
+  BUILD_ARCHS_VALUE="arm64 x86_64"
+fi
 IFS=' ' read -r -a BUILD_ARCHS <<< "$BUILD_ARCHS_VALUE"
 PRIMARY_ARCH="${BUILD_ARCHS[0]}"
 SPARKLE_PUBLIC_ED_KEY="${SPARKLE_PUBLIC_ED_KEY:-AGCY8w5vHirVfGGDGc8Szc5iuOqupZSh9pMj/Qs67XI=}"