Slat

Your windows, neatly in a row.

Slat is a scrolling tiling window manager for macOS. Every window gets its own column, and the columns sit side by side in a row that's wider than your screen. Opening a window adds it to the row without shrinking the others, and moving focus slides the row just far enough to show it.

Slat is written in Rust, free, and MIT licensed. It lives in the menu bar and runs its window engine as a separate process, so a crash in one never takes down the other.

See it move

Move focus. The row slides just far enough to show the window you picked.	Open anything. New windows join the row next to the one you're using. Nothing else shrinks.
Move windows. Carry the focused window left or right, one place at a time.	Cycle width. Step a window through ½, ⅔ and full. Its neighbours make room.
Stack. Pile windows into one column, then pop them back out.	Workspaces. A separate row per task, one above the other. Switching is instant.
Swipe. Four fingers on the trackpad slide the row, or hold a key and use the scroll wheel.	Canvas. Windows keep their own size and spot on one long desk, and you slide the desk.

The keycaps show the default mod key, ⌃⌥. You can switch it to ⌥ or ⌘⌥ in Settings.

Install

1. Download Slat.zip from the latest release and move Slat.app to /Applications.
2. Slat isn't notarized by Apple, so the first launch needs a right-click on Slat.app, then Open. You can also clear the download flag in Terminal:

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

3. Grant Accessibility access when onboarding asks. macOS requires it before any app can move other apps' windows. Slat never reads what's inside them.

Updates install from the menu bar with one click. Slat checks GitHub once a day and verifies every download against a signing key built into the app before swapping it in. Each release is signed with the same certificate, so you keep your Accessibility permission across updates.

Shortcuts

The default mod key is ⌃⌥. Settings › Shortcuts switches it to ⌥ or ⌘⌥.

Keys	Action
mod + H J K L or arrows	Focus left, down, up, right
mod + ⇧ + H J K L or arrows	Move the window
mod + R / mod + ⇧ + R	Cycle the width through your presets, or step it narrower
mod + F	Full width
mod + C	Center the window
mod + T	Float or tile the window
mod + ⇧ + T	Show the column as tabs
mod + [ / ]	Stack into the column on the left or right
mod + ⇧ + [ / ]	Pop out of a stack to the left or right
mod + N	Send to the other display
mod + 1...9	Go to a workspace
mod + ⇧ + 1...9	Take the window to a workspace

You can also swipe with four fingers, or hold ⌥ and turn the scroll wheel, to slide the row.

Features

• Columns layout. New windows open at a width you pick (¼ to full). Cycle width steps through presets.
• Canvas layout. One long desk. Windows keep their own size and position, and you slide the whole desk. Drag a window anywhere and it stays put. Positions are saved and come back after a restart.
• Virtual workspaces. Up to nine rows per display, stacked one above the other inside one macOS Space, so switching is instant.
• Gestures. Three- or four-finger swipes with natural or reversed direction and adjustable sensitivity.
• App rules. Make an app always float or open at a fixed width.
• Mac Setup check. Slat watches for settings that break tiling, like Stage Manager, shared Spaces across displays, or another window manager running, and links to the fix.
• Focus follows mouse, mouse follows focus, dim inactive windows, gaps.
• Custom config. Flip one switch and edit the engine's engine.toml by hand. The engine reloads it on save. An existing Paneru config can be imported.

Settings live in ~/Library/Application Support/Slat/, and logs in ~/Library/Logs/Slat/.

Build from source

You need Rust (stable) and the Xcode command line tools.

scripts/bundle.sh          # dist/Slat.app for this Mac
UNIVERSAL=1 scripts/bundle.sh   # arm64 + x86_64

The repo has two crates:

• app/ is the menu bar app and its windows (Slat). The menu bar uses native NSStatusItem menus, and the windows use egui.
• engine/ is the window engine (slat-engine), a fork of Paneru. See engine/README.md for what the fork adds.

Run the tests with cargo test in each crate.

Releasing

Write release-notes/vX.Y.Z.md, bump version in app/Cargo.toml, then push a vX.Y.Z tag. CI builds a universal app, signs it, signs the update archive, and publishes the release. Installed copies pick it up within a day.

The workflow needs three repository secrets: MINISIGN_SECRET_KEY, CODESIGN_P12 (base64) and CODESIGN_P12_PASSWORD.

Credits

The window engine is based on Paneru (MIT), Copyright (c) 2025 Karinushka@github. Slat is MIT licensed. See LICENSE.