LockPaw

Cover your screen with a hotkey. AI agents keep running. Touch ID to unlock.
Think Tesla Dog Mode — but for your Mac.

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Lock + Paw. Your screen's faithful guard dog.

Features

• ⌨️ One hotkey — lock and unlock with ⌘⇧L (customizable)
• 🔒 Touch ID unlock — or password fallback, just like your Mac
• 🖥️ Every screen covered — all displays, auto-detects new monitors
• 🤖 Agents keep running — AI coding tools, builds, downloads, SSH sessions
• 😴 Prevents sleep — IOKit assertion keeps your Mac awake while locked
• 📦 3.4 MB — native Swift, no Electron, no frameworks
• 🚫 No analytics — no data leaves your Mac, no accounts, no internet required
• 🐕 The watchdog — a metallic origami dog in breathing teal light guards your screen

Usage

Action	How
Lock	Your hotkey (default Cmd+Shift+L)
Quick unlock	Same hotkey
Fallback unlock	Tap screen → Touch ID or password
Settings	Menu bar → Settings…
Change hotkey	Settings → Shortcuts → click to record

Install

Download

Grab the latest signed & notarized DMG from getlockpaw.com or GitHub Releases.

Homebrew

brew tap sorkila/lockpaw
brew install --cask lockpaw

Build from source

brew install xcodegen
git clone https://github.com/sorkila/lockpaw.git
cd lockpaw
xcodegen generate
xcodebuild -scheme Lockpaw -configuration Release build

On first launch, grant Accessibility when prompted. A dog icon appears in your menu bar.

Design

The lock screen is intentionally minimal. Near-black canvas. Subtle radial glow. One element at a time.

Progressive disclosure — the screen opens with the watchdog, your message, and a quiet elapsed timer. A chevron breathes at the bottom. Tap anywhere to reveal the fallback auth button. Nothing appears without your intent.

The watchdog — a metallic origami dog rendered in teal and amber, floating in a pool of light. Slow 12-second breathing cycle. On successful unlock, the dog scales up with a teal bloom and fades away.

Typography — system San Francisco throughout. Regular weight message at 55% white. Monospaced timer at 35%. The screen whispers.

Auth button — glass material effect with a subtle border. Visible enough to be tappable, quiet enough to stay out of the way.

Under the hood

Hotkey — CGEvent.tapCreate with .listenOnly on a dedicated background thread. Bypasses the LSUIElement activation issue that affects Carbon hotkeys in menu bar apps. Requires Accessibility permission.

Input blocking — separate CGEventTap intercepts all keyboard, scroll, and tablet events system-wide while locked. Mouse events pass through to the overlay (SwiftUI buttons need clicks). If macOS disables the tap, it re-enables synchronously in the callback.

Window level — CGShieldingWindowLevel(), the highest level in the system. Above Spotlight, Notification Center, screen savers, everything.

Multi-display — one overlay window per screen, recreated on hot-plug.

State machine — LockState enum with validated transitions. Every transitionTo() call is checked. State is verified again after async authentication returns.

Sleep prevention — IOPMAssertion keeps the Mac awake while locked.

Auth — LAContext.evaluatePolicy(.deviceOwnerAuthentication) for Touch ID with password fallback. Rate-limited: 30s cooldown after 3 failed attempts.

Auto-updates — Sparkle framework checks for updates automatically. Appcast hosted at getlockpaw.com.

Security model

Lockpaw is a visual privacy tool, not a security boundary.

It guards against the accidental — a colleague, a cat, your own muscle memory while agents run. Not the intentional.

What it does

• Overlay at highest system window level
• Event tap blocks all keyboard/scroll input
• Fast User Switching cancels auth, keeps lock active
• Accessibility revocation detected and handled (force unlock with warning)
• URL scheme rate-limited (100ms debounce)
• Debug escape hatch compile-gated (#if DEBUG)
• State machine validates every transition
• Hotkey conflict detection against system shortcuts

What it doesn't do

• Prevent pkill Lockpaw
• Block synthetic events (AppleScript, Accessibility API)
• Survive kernel-level access
• Protect against screen recording during overlay fade-in

For real security: Ctrl+Cmd+Q.

URL scheme

lockpaw://lock              Lock the screen
lockpaw://unlock            Unlock with Touch ID
lockpaw://unlock-password   Unlock with password
lockpaw://toggle            Toggle lock state

Architecture

Lockpaw/
├─ LockpawApp                     Entry, MenuBarExtra, AppDelegate, onboarding
├─ Controllers/
│  ├─ LockController              State machine, lock/unlock orchestration
│  ├─ Authenticator               LAContext · Touch ID · password fallback
│  ├─ InputBlocker                CGEventTap · keyboard/scroll blocking
│  ├─ HotkeyManager              CGEventTap · global hotkey detection
│  ├─ OverlayWindowManager       NSWindow · multi-display · shielding level
│  └─ SleepPreventer             IOKit · idle sleep assertion
├─ Models/
│  ├─ LockState                  .unlocked → .locking → .locked → .unlocking
│  └─ HotkeyConfig               Centralized hotkey UserDefaults access
├─ Views/
│  ├─ LockScreenView             Dog · glow · progressive disclosure
│  ├─ MenuBarView                Dropdown · lock/unlock/quit
│  ├─ SettingsView               Native Form · hotkey recorder · appearance
│  └─ OnboardingView             4-step wizard · hotkey · accessibility
├─ Utilities/
│  ├─ Constants                  Timing, animations, formatting
│  ├─ Notifications              All Notification.Name in one place
│  └─ AccessibilityChecker       AXIsProcessTrusted + System Settings
└─ Resources/
   └─ Assets                     App icon, mascot, menu bar icon, colors

CI

Pushes to main and PRs run build + 34 unit tests via GitHub Actions. Tagged releases (v*) build, sign, notarize, and create GitHub Releases with the DMG attached.

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_{getlockpaw.com}