Free, open-source Alt-Tab for Mac: a window switcher that lets you hide the apps you don't need.
⌥ ⇥ to switch windows · type to search · ⌫ to hide an app

English · Português

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Tern is a free, native macOS window switcher (an Alt-Tab for Mac) that lives in the menu bar, with no Dock icon. A global shortcut opens a HUD to cycle through and focus open windows — in the spirit of alt-tab.app, with one twist: you can hide an app (or a single window) and it stays out of the switcher until you take it off the list.

Type-to-search is included, not a paid add-on. Example: five apps open, one on the exclusion list, and the shortcut shows only the other four.

Tern vs AltTab

Both are open-source window switchers for Mac. AltTab is the established one: notarized, Space badges, full-size previews. Its type-to-search is a Pro feature. Tern ships search for free and is built around hiding apps, windows, title rules, snooze, and Focus modes. Tern is not notarized yet, so the first launch needs Open Anyway. A longer comparison is on the site.

FAQ

Does the Mac have Alt-Tab? No. ⌘⇥ switches apps, not windows. Tern uses ⌥⇥ to switch window by window.

Why Accessibility? macOS only lets an app read window titles and bring a window forward with Accessibility on. Tern does not read window contents.

Why the first-launch warning? The app is signed with its own certificate, not Apple notarization. Grant Open Anyway once; later updates do not ask again. Step-by-step: Help.

Download

Get Tern-x.y.z.dmg from the latest release, open it, and drag Tern into Applications.

The app isn't notarized by Apple yet, so macOS blocks the first launch. Open Tern once, dismiss the warning, then go to System Settings › Privacy & Security › Open Anyway. Or run:

xattr -dr com.apple.quarantine /Applications/Tern.app

Then grant Accessibility when Tern asks and press ⌥⇥.

Features

• Menu bar app (LSUIElement), Swift + SwiftUI/AppKit.
• Configurable global shortcut (default ⌥⇥). The HUD floats over the frontmost app, and the shortcut doesn't also fire in your browser. Hold the modifier and tap the key again to move forward; release the modifier to focus the window. ⇧⇥ moves back. Click, ⏎, and esc work too.
• Type to search: with the switcher open, type to filter windows by app name and title ("vsc" finds Visual Studio Code).
• Window actions: ⌘W closes the highlighted window, ⌘M minimizes it, ⌘Q quits its app.
• Exclusion by bundle id (the main path), by window (bundle id + title), and by title rule (text or * pattern, in one app or any app).
• Snooze: ⇧⌫ hides an app for an hour; in Settings, hide for 1 hour, until tomorrow, or always.
• Modes: named sets of extra apps to hide (Work, Personal…), switched from the menu bar or automatically by a macOS Focus through a Focus Filter.
• Automation: Shortcuts actions and a tern:// URL scheme (see below).
• Live preview of each window on its card (with Screen Recording permission).
• UI in English and Portuguese (follows the macOS language; other languages fall back to English).
• Exclusions and shortcut persisted in UserDefaults.
• Settings to record the shortcut, grant Accessibility, and add or remove exclusions.

In the switcher: ⌫ hides the highlighted window's app, ⇧⌫ hides it for an hour, ⌥⌫ hides just that window. While searching, ⌫ edits the search instead.

Requirements

• macOS 13 Ventura or later
• Xcode 15 or later (to build from source)
• A free Apple ID to sign the app locally

Build and run

git clone https://github.com/gitlherme/tern.git
cd tern
open Tern.xcodeproj

In Xcode:

1. Pick the Tern scheme.
2. Under TARGETS › Tern › Signing & Capabilities, check Automatically manage signing and choose your Personal Team. With a stable signature, Accessibility and Screen Recording permissions survive rebuilds.
3. Run (⌘R). Tern shows up in the menu bar, not the Dock.

From the command line:

xcodebuild -project Tern.xcodeproj -scheme Tern -configuration Debug -destination 'platform=macOS' build

Install for daily use

Product › Archive › Distribute App › Custom › Copy App, then move Tern.app into /Applications. Add it under System Settings › General › Login Items.

Permissions

Accessibility (required)

macOS only lets Tern read window titles and bring the chosen window to the front with Accessibility on.

1. Run Tern.
2. Press ⌥⇥ (or your recorded shortcut). If the permission is off, the HUD asks for Accessibility.
3. Click Open System Settings (or Request permission for the native prompt).
4. System Settings → Privacy & Security → Accessibility.
5. Turn on Tern. If it isn't listed, click + and choose Tern.app from DerivedData or Xcode's Products folder.
6. Go back to Tern and use the shortcut again.

If you rebuild with a different path or signature, macOS treats it as a new app: toggle Tern off and on in the list, or remove it and add it again.

Direct links (Ventura/Sonoma/Sequoia):

• x-apple.systempreferences:com.apple.preference.security?Privacy_Accessibility
• x-apple.systempreferences:com.apple.settings.PrivacySecurity.extension?Privacy_Accessibility

Input Monitoring (only if the shortcut leaks)

With Accessibility on, Tern installs an event tap and swallows the shortcut so ⌥⇥ doesn't also run in your browser. On most macOS versions that's enough.

If the frontmost app still reacts to the shortcut, turn on Input Monitoring for Tern:

System Settings → Privacy & Security → Input Monitoring.

• x-apple.systempreferences:com.apple.preference.security?Privacy_ListenEvent

Screen Recording (previews)

Cards show a thumbnail of each window, which macOS gates behind Screen Recording. Without it the switcher still switches windows; only the preview goes away.

1. In Tern Settings, click Request permission (or Show Tern.app in Finder). This selects Tern in Finder. When run from Xcode, it first copies the app to ~/Applications/Tern.app, since the Settings + button can't reach DerivedData.
2. System Settings → Privacy & Security → Screen & System Audio Recording.
3. Tern doesn't add itself to this list. Click +, choose Tern.app (the one selected in Finder) or drag it into the list, and turn the switch on.
4. Menu bar → Quit, then run Tern again. The new permission only applies to the next process.

With "Sign to Run Locally" (adhoc signature), every rebuild changes the cdhash and the switch may need to be turned on again. Signing with your Personal Team avoids that.

• x-apple.systempreferences:com.apple.preference.security?Privacy_ScreenCapture
• x-apple.systempreferences:com.apple.settings.PrivacySecurity.extension?Privacy_ScreenCapture

Usage

1. Grant Accessibility. For previews, grant Screen Recording too.
2. ⌥⇥ opens the switcher with the current window at index 0 and the previous one at 1. Release ⌥ to jump to the previous window; ⇥ moves further back in recency. Minimized windows come last and are restored when focused.
3. Keep going with ⇥ / arrow keys, release ⌥ to focus, or click a card.
4. Start typing to search. Once you type, releasing ⌥ no longer confirms: ⏎ opens, esc clears the search.
5. To hide an app: Settings → Exclusions → Add running app…, or ⌫ in the switcher (⇧⌫ for an hour).
6. To hide a single window: Add open window… or ⌥⌫. To hide windows whose title changes, add a title rule.
7. Modes: Settings → Modes. To link one to a Focus, go to System Settings › Focus › (a Focus) › Focus Filters › Add Filter › Tern.
8. Menu bar: Open switcher, Mode, Settings, Check for Updates, Quit.

Automation

Shortcuts app actions: Open Tern switcher, Hide app in Tern (always, 1 hour, until tomorrow), Show app in Tern, and Set Tern mode.

URL scheme, for scripts, Raycast, or anything that opens links:

URL	Does
tern://open	Opens the switcher
tern://hide?app=com.spotify.client	Hides an app (add &for=1h or &for=tomorrow to snooze)
tern://unhide?app=com.spotify.client	Shows it again
tern://mode?name=Work	Turns on a mode; tern://mode turns it off

Any web page can open a tern:// link, so URLs only do harmless things: nothing closes windows or quits apps.

Don't record ⌘⇥: macOS reserves it for the app switcher.

Known limitations

• Order is by recency: current window → previous → other recently used → minimized last.
• Window exclusions match the exact title: if it changes, the window shows up again. Title rules cover that case.
• Doesn't replace the system's ⌘⇥.
• No sandbox: utilities like this need to talk to other apps' windows, which also rules out the Mac App Store.

Project structure

Tern.xcodeproj           Xcode project
Tern/
  TernApp.swift          SwiftUI entry point, no Dock icon
  AppModel.swift         state, shortcut, exclusions
  Localizable.xcstrings  UI strings (pt-BR source → en)
  Models/                window, exclusion, shortcut
  Services/              AX windows, CG metadata, previews, Carbon hotkey, persistence
  Views/                 HUD, settings, menu bar
brand/                   icon, wordmark, and variants
site/                    landing page (static HTML, pt-BR and en/)

Bundle id: dev.guilhermevieira.Tern. Deployment target: macOS 13+.

License

MIT © Guilherme Vieira. Free and open source: use, modify, and redistribute it as you like.