Disable & enable screens · Force HiDPI · brightness with EDR boost · color warmth (with auto-night) · window tiling/snapping · transparency, blur, keep-on-top & picture-in-picture · keep-awake · remote access.

Features · Screenshots · Install · Requirements · How it works · FAQ · Support · License

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Note

One mug in your menu bar instead of a stack of paid utilities - free and open-source, under 1 MB, with no telemetry, no subscription, and no background daemon. Built entirely on Apple's own (private) frameworks; nothing is bundled or phoned home.

Features

Disable / enable any display	Turn off the built-in panel in clamshell/headless setups so it stays off when the lid opens. Optionally auto-disable the built-in whenever an external monitor connects - with a failsafe that re-enables the built-in if a disconnect (or a stale/phantom external entry) would otherwise leave you with no usable screen.
⤢ Force HiDPI	Add crisp scaled (retina) resolutions to displays that don't natively offer them, via a mirrored private SLVirtualDisplay, plus a "More Space" supersampling tier. Optionally writes persistent "crisp HiDPI" override plists.
Brightness + boost	Built-in panel via DisplayServices, externals via DDC/CI, an inline auto-brightness toggle, and an EDR boost above 100% clamped to the display's real, learned headroom (mild on a built-in, big on a true XDR/HDR panel) - colors preserved, auto-suspends in Mission Control.
Warmth + auto-night	Per-display color-temperature slider (f.lux / Night-Shift style) via gamma ramps - 6500 K neutral → ~3400 K warm, persisted, restores native ColorSync at 0%. An automatic night schedule (moon toggle) eases warmth on at dusk and off by morning, hands-free.
Window snapping	Tile the focused window to halves, quarters, thirds / two-thirds, maximize, center, or restore - via global ⌃⌥ keyboard shortcuts, dragging to a screen edge/corner (with a live preview), or the Window menu. Uses the Accessibility API; works on a stock machine.
Window arrangement	Tile every window on the screen at once: a 2×2 grid, or one window centered over the grid (the others peek out around its edges). Toggle layouts, promote the focused window to the center, or rotate which window is centered - on global ⌃⌥⇧ shortcuts or the Window → Arrange Windows menu. Same Accessibility permission as snapping.
Window transparency	Set per-app or all-window opacity for any app, via a self-contained scripting addition injected into Dock (no external tools). Optional frosted-glass blur, per-app Keep on top, and Picture-in-Picture (shrink a window into a still-usable floating corner).
Keep awake	An IOKit caffeine assertion so the Mac and its display don't sleep - indefinitely (toggle) or for a set duration (15 min → 5 h). Replaces KeepingYouAwake.
Remote access	Reach this Mac - and your other Macs - from anywhere, with nothing to install. An auto-reconnecting reverse-SSH tunnel through a relay host you control forwards SSH, Screen Sharing, and file transfer (SFTP); no Tailscale/Headscale or third-party agent. Doubles as a client: peers on the same relay are auto-discovered with live online status, so you can Screen Share, SSH, or transfer files to them from the menu. Optionally keeps the Mac awake while on so it stays reachable, and surfaces why a connection failed.
Text smoothing	Toggle macOS's grayscale antialiasing on/off - a single system-wide switch that affects every display, including the built-in (AppleFontSmoothing isn't per-display). The effect is most visible on non-Retina, external, or scaled monitors; on a Retina panel it's subtle by design. (macOS treats the setting as binary - the old strength levels render identically.) Applies after a re-login.

The menu-bar icon is an interactive coffee mug: left-click toggles keep-awake (filled cup = awake), right-click opens the menu.

Screenshots

The menu-bar mug - an empty cup when idle, filled while keeping your Mac awake (left-click to toggle, right-click for the menu):

The menu - a Keep Awake row with an inline toggle, per-display Brightness (with the inline Ⓐ auto-brightness toggle) and Warmth sliders (with the **** auto-night toggle), a Window snapping section, a Remote Access row, and per-app Transparency rows with frosted-glass, keep-on-top, and picture-in-picture toggles:

Light, color & transparency - per-display Brightness (with the EDR boost above 100%) and Warmth (with the auto-night toggle), and per-app opacity, keep-on-top and picture-in-picture:

Remote access - set the relay inline as a single user@host:port, copy this Mac's relay key, keep the Mac awake while on, and Screen Share / SSH / transfer files to your auto-discovered Macs (● live · ○ offline), all from the menu. If a connection fails it tells you why (here the placeholder relay.example.com doesn't resolve):

Window snapping - tile the focused window to halves, quarters, thirds, maximize or center, each with a layout glyph and a global ⌃⌥ shortcut:

Window arrangement - tile every window into a 2×2 grid, or float one centered over the grid (the rest peek out around it); cycle layouts, promote, or rotate the centered window with ⌃⌥⇧ shortcuts:

Submenus - Keep-Awake durations, the curated Resolution picker (= panel-native), the Force HiDPI "More Space" tier, and the grouped Settings:

Install

Homebrew (cask):

brew install --cask oabdrabo/tap/displaydeck

From source

git clone https://github.com/oabdrabo/DisplayDeck.git
cd DisplayDeck
make install      # builds, signs, copies to /Applications, launches

Needs Xcode Command Line Tools (xcode-select --install). Other targets: make (build only), make zip (release artifact), make clean, make uninstall.

It launches at login by default - toggle that under the menu-bar icon → Settings → Launch at Login. The app is self-signed (not notarized), so Gatekeeper may warn on first open. The Homebrew cask strips the quarantine flag for you, so it just opens. If you installed it manually, either run xattr -dr com.apple.quarantine /Applications/DisplayDeck.app, or open System Settings → Privacy & Security → Open Anyway (on macOS 15+ the old right-click → Open no longer works).

Uninstall

brew uninstall --cask displaydeck      # if installed via Homebrew

From source, or to remove the Dock scripting addition installed for transparency:

make uninstall      # removes the app + (with admin) the scripting addition & sudoers entry

Requirements

• macOS 14+ on Apple Silicon.
• Window transparency / blur / keep-on-top need SIP disabled and the -arm64e_preview_abi boot-arg - these allow injecting the payload into Dock. First use prompts once for an admin password to install the scripting addition; afterwards it loads silently. (Display / HiDPI / brightness / warmth work without them.)
• Window snapping and Picture-in-Picture ask for Accessibility permission once (no SIP changes needed).
• Remote access needs a relay host you can SSH into (e.g. a cheap VPS or your homelab box) with a forwarding-only tunnel user; nothing is installed on it beyond an authorized_keys line. It uses macOS's built-in /usr/bin/ssh plus the system Remote Login and Screen Sharing toggles (enabled for you on first use).

How it works

• Disabling uses the private CGSConfigureDisplayEnabled; Force HiDPI mirrors the panel onto a private SLVirtualDisplay pinned to the desired logical size, and "crisp HiDPI" writes display-override plists under /Library/Displays/.../Overrides.
• Transparency injects a payload into Dock (task_for_pid + an arm64e bootstrap) that calls SLSSetWindowAlpha / SLSSetWindowBackgroundBlurRadius / SLSSetWindowLevel over a private unix socket. The injection technique is adapted from yabai (MIT); see sa/loader.m.
• Warmth loads per-channel gamma ramps with the public CGSetDisplayTransferByTable; the brightness boost is a borderless EDR overlay (CAMetalLayer, multiply blend) clamped each frame to the live maximumExtendedDynamicRangeColorComponentValue.
• Picture-in-Picture resizes/moves the real window through the Accessibility API (AXUIElement) and reuses Keep-on-top for the float.
• Window snapping moves/resizes the focused window through the same AXUIElement API; global shortcuts are registered as Carbon RegisterEventHotKey hot keys, and drag-to-snap watches a global mouse monitor to detect edge/corner drops.
• Remote access spawns /usr/bin/ssh -N -R … to publish this Mac's SSH/Screen-Sharing ports on relay loopback ports (derived from the hostname), auto-reconnecting via NSTask. Peer discovery is a read-only forced command on the relay that lists every authorized Mac's name and ports; connecting opens a -L forward to vnc://localhost or a ProxyJump SSH session.

Because these are private APIs, behaviour can change between macOS releases.

Project layout

src/
  main.m              app entry point
  app/                AppDelegate - status item, menu, UI
  display/            DisplayManager, HiDPIInjector, Brightness,
                      BrightnessBooster (EDR boost), ColorTemperature (warmth)
  transparency/       WindowTransparency - in-app client for the Dock payload
  window/             WindowPiP - picture-in-picture; WindowManager - tiling/snapping
  power/              Caffeine - keep-awake power assertion
  remote/             RemoteAccess - reverse-SSH tunnel, relay config, peer discovery
  common/             DDUtil - shared error/AppleScript helpers
sa/                   scripting addition injected into Dock (loader.m, payload.m)
tools/                build_icon.m - generates AppIcon.icns
resources/            Info.plist

FAQ

Will this harm my Mac? No. It uses Apple's own frameworks (no kernel extensions), and everything it does is reversible - displays re-enable, warmth and brightness reset, windows restore, and quitting the app undoes the live overlays.

Is the brightness boost real, or just a dimming trick? Real. It's an EDR (extended dynamic range) overlay that drives the panel past its normal 100%, clamped each frame to the display's actual headroom - modest on a standard panel, large on an XDR/HDR one. Colors are preserved, and it auto-suspends during Mission Control.

Why does window transparency need SIP disabled? Making another app's window transparent means injecting a small payload into Dock, which macOS only permits with SIP off plus the -arm64e_preview_abi boot-arg. Everything else - display control, HiDPI, brightness, warmth, keep-awake - works on a stock machine.

Does it run on Intel Macs? No - Apple Silicon only. The boost relies on EDR and the Dock-injection path is arm64e.

Will updating reset my settings? No. Brightness, warmth, and per-app preferences live in your user defaults and persist across updates.

Contributing

Issues, ideas, and PRs are welcome - see CONTRIBUTING.md for build, test, and PR guidelines. Since everything rides on private macOS APIs, real-device verification is especially valued.

Support & sponsors

DisplayDeck is free, open-source, and has no tracking or ads. If it's useful to you, you can support continued development - pay what you like, once or monthly:

 

License

MIT © 2026 Omar Abdrabo