diff --git a/CLAUDE.md b/CLAUDE.md
index c0e38f1..ee8e5a4 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -14,10 +14,10 @@ A native macOS app that shows video from a capture device (camera / capture card
 ## Structure
 - `Sources/` – app code (AppKit + AVFoundation, one `AVCaptureSession`, audio via `AVCaptureAudioPreviewOutput`). The `App` class is split into extensions:
   `main.swift` (entry point), `App.swift` (state, window, lifecycle), `Capture.swift` (devices, formats, hot-plug), `Menu.swift` (menus and actions), `Power.swift` (sleep prevention), `Preferences.swift` (UserDefaults-backed settings).
-- `Config/Info.plist`, `Config/SecondDisplay.entitlements` – version, permissions (camera, microphone; hardened runtime).
+- `Config/Info.plist`, `Config/SecondDisplay.entitlements`, `Config/dmg/` – version, permissions (camera, microphone; hardened runtime).
 - `Resources/` – `AppIcon.icon` (Icon Composer, Liquid Glass; compiled by `actool`), `{en,pl}.lproj` (`Localizable.strings`, `InfoPlist.strings`), `uninstall.sh` (copied into the bundle; removes the app, preferences, caches, TCC permissions). Bundle ID: `com.mmacierzanka.seconddisplay`.
 - `scripts/check-strings.sh` – en/pl translation consistency.
-- `Makefile` – `make` (builds `build/SecondDisplay.app`), `run`, `check`, `install`, `uninstall`, `clean`, `help`. `SIGN_ID` defaults to ad-hoc (`-`).
+- `Makefile` – `make` (builds `build/SecondDisplay.app`), `run`, `check`, `install`, `uninstall`, `dmg`, `clean`, `help`. Builds are universal (arm64 + x86_64, macOS 26+). `make dmg` makes an un-notarized DMG with `Config/dmg/Read Me First.txt`. `SIGN_ID` defaults to ad-hoc (`-`).
 
 ## Conventions
 - Settings live in `UserDefaults` (keys: `video`, `audio`, `keepAwake`, `startFull`, `onTop`, `gravity`, `format.<id>`).
diff --git a/Config/dmg/Read Me First.txt b/Config/dmg/Read Me First.txt
new file mode 100644
index 0000000..0825ff0
--- /dev/null
+++ b/Config/dmg/Read Me First.txt	
@@ -0,0 +1,32 @@
+SECOND DISPLAY — INSTALLATION
+=============================
+
+1. Drag "SecondDisplay" onto the "Applications" folder in this window.
+
+2. Open Second Display from Applications.
+   macOS will most likely refuse: this app is not notarized by Apple
+   (the author does not pay for a developer account). The app is safe to
+   run if you trust where you got it — the source code is open.
+
+3. Allow it once (pick ONE way):
+
+   A) System Settings
+      - Open System Settings > Privacy & Security.
+      - Scroll to the Security section; you will see
+        "SecondDisplay was blocked...". Click "Open Anyway".
+      - Confirm with your password / Touch ID, then click "Open".
+
+   B) Terminal
+      xattr -dr com.apple.quarantine /Applications/SecondDisplay.app
+
+   You only need to do this once per downloaded copy.
+
+4. On first launch, allow Camera and Microphone access.
+   (Change later in System Settings > Privacy & Security.)
+
+REQUIREMENTS
+  macOS 26 or newer.
+
+UNINSTALL
+  Run this in Terminal to remove the app and every trace it leaves:
+    /Applications/SecondDisplay.app/Contents/Resources/uninstall.sh
diff --git a/Makefile b/Makefile
index 71a168f..bfefc4c 100644
--- a/Makefile
+++ b/Makefile
@@ -5,12 +5,18 @@ RES      := $(shell find Resources -type f)
 SIGN_ID  ?= -
 BUILDNUM := $(shell git rev-list --count HEAD 2>/dev/null || echo 1)
 
-.PHONY: build run clean install uninstall check help
+VERSION  := $(shell /usr/libexec/PlistBuddy -c "Print :CFBundleShortVersionString" Config/Info.plist)
+DMG      := build/SecondDisplay-$(VERSION).dmg
+
+.PHONY: build run clean install uninstall check dmg help
 build: $(APP) ## Build build/SecondDisplay.app
 
 $(APP): Makefile $(SRC) $(RES) Config/Info.plist Config/SecondDisplay.entitlements
 	rm -rf $(APP) && mkdir -p $(APP)/Contents/MacOS $(APP)/Contents/Resources
-	swiftc -O $(SRC) -o $(APP)/Contents/MacOS/SecondDisplay
+	swiftc -O -target arm64-apple-macos26.0 $(SRC) -o $(APP)/Contents/MacOS/SecondDisplay-arm64
+	swiftc -O -target x86_64-apple-macos26.0 $(SRC) -o $(APP)/Contents/MacOS/SecondDisplay-x86_64
+	lipo -create $(APP)/Contents/MacOS/SecondDisplay-* -output $(APP)/Contents/MacOS/SecondDisplay
+	rm $(APP)/Contents/MacOS/SecondDisplay-*
 	cp Config/Info.plist $(APP)/Contents/Info.plist
 	/usr/libexec/PlistBuddy -c "Set :CFBundleVersion $(BUILDNUM)" $(APP)/Contents/Info.plist
 	cp -R Resources/en.lproj Resources/pl.lproj Resources/uninstall.sh $(APP)/Contents/Resources/
@@ -36,5 +42,14 @@ check: build ## Lint sources, plists, strings and the built bundle
 	scripts/check-strings.sh
 	codesign --verify --strict $(APP)
 
+dmg: build ## Build a distributable disk image (not notarized)
+	rm -rf build/dmg $(DMG) && mkdir build/dmg
+	cp -R $(APP) build/dmg/
+	ln -s /Applications build/dmg/Applications
+	cp "Config/dmg/Read Me First.txt" build/dmg/
+	hdiutil create -volname "Second Display" -srcfolder build/dmg -ov -format UDZO $(DMG)
+	hdiutil verify $(DMG)
+	rm -rf build/dmg
+
 help: ## List targets
 	@grep -E '^[a-z]+:.*##' Makefile | sed 's/:.*##/ -/'
diff --git a/README.md b/README.md
index 8bc7f1c..0f085bd 100644
--- a/README.md
+++ b/README.md
@@ -11,6 +11,7 @@ make          # builds build/SecondDisplay.app
 make run      # build and launch
 make check    # lint: typecheck, plists, translations, signature
 make install  # copy to ~/Applications
+make dmg      # build/SecondDisplay-<version>.dmg (universal, not notarized)
 make help     # list targets
 ```
 The app is signed ad-hoc (works on this Mac). For distribution: `make SIGN_ID="Developer ID Application: ..."` (notarization is still required).
@@ -25,14 +26,17 @@ open ~/Applications/SecondDisplay.app
 ```
 On first launch macOS asks for camera and microphone access — allow both. You can change this later in System Settings → Privacy & Security.
 
-If you received a prebuilt copy that is not notarized, macOS blocks it. Allow it once in System Settings → Privacy & Security → "Open Anyway", or run `xattr -dr com.apple.quarantine SecondDisplay.app`.
+If you received a prebuilt copy (the `.dmg`), drag the app to Applications. It is not notarized, so macOS blocks it on first launch: allow it once in System Settings → Privacy & Security → "Open Anyway", or run `xattr -dr com.apple.quarantine /Applications/SecondDisplay.app`. The same steps are in `Read Me First.txt` inside the disk image.
+
+## Releasing a DMG
+`make dmg` builds a universal (arm64 + x86_64) app and packs it with an `Applications` shortcut and `Read Me First.txt` (source: `Config/dmg/`). The disk image is not signed with a Developer ID or notarized; the instructions in it explain how recipients allow it. Bump the version in `Config/Info.plist` before releasing and tag it (`git tag -a vX.Y.Z -m vX.Y.Z`).
 
 ## Usage
 Menus at the top of the screen: **Video** (device, format), **Audio** (source or off), **Options** (prevent display sleep, start in full screen, always on top, mute ⇧⌘M, scaling), **Window** (tiling, full screen ⌃⌘F).
 
 ## Layout
 - `Sources/` – the app (AppKit + AVFoundation): `App` (state, window), `Capture` (devices, formats), `Menu`, `Power`, `Preferences`, `main` (entry point)
-- `Config/` – `Info.plist`, entitlements (camera, microphone)
+- `Config/` – `Info.plist`, entitlements (camera, microphone), `dmg/` (instructions shipped in the disk image)
 - `Resources/` – icon (`AppIcon.icon`, Icon Composer), en/pl translations, `uninstall.sh`
 - `scripts/check-strings.sh` – translation consistency