SpacialShell

material-shell's spatial desktop, on the Mac. A tiling window manager where every window has one address, you move by direction, and the shell remembers where you put things.

Live capture: the rail on the left, the tab bar on top, tiled windows below. Fn+Space cycles layouts, Fn+A/Fn+D move along the row, Fn+W/Fn+S move between rows.

Install Keybindings Config reference

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Why space works

Your brain is already a very good window manager, if you give it a place to work with. Two everyday mental mechanisms do the heavy lifting:

• Spatial memory: remembering where things are in a space you know. You don't search your kitchen for the mugs; your hand goes to the cupboard.
• Mental mapping: holding a picture of that space in your head and planning a route through it.

A pile of overlapping windows gives neither anything to hold on to. A stable grid gives both everything they need. So SpacialShell:

1. Lays your apps out in two dimensions, grouped by use case, category or project: browsers on one row, editor and terminal on the next, Spotify and VLC below.
2. Remembers that layout on the fly. No config to write; you build the arrangement by using it, and it survives a reboot.
3. Moves by direction, like a game world: up, down, left, right. No hunting through lists.
4. Shows the whole map at a glance, so the mouse is as good a way around as the keyboard.

Finding a window stops being a search and becomes wayfinding.

Built for macOS, not Linux

material-shell extended GNOME Shell, and its successor Veshell is its own Wayland environment. Both own the compositor. On a Mac nobody does, and that shapes everything here:

• The Accessibility API instead of a compositor. Windows are moved and sized through the same public AX interface screen readers use. It asks for Accessibility and nothing more.
• Screenshot-proxy animations. macOS has no hooks for animating another app's window, so a switch captures the windows, slides the pictures, and moves the real windows once at the end.
• Living beside Spaces, fullscreen and the menu bar, rather than replacing them. A fullscreen window keeps its tab, and an app can't pull you out of a fullscreen Space by grabbing focus.
• No private APIs, SIP stays on. No scripting addition to reinstall after every macOS update.
• Notarised, outside the App Store, because the App Store sandbox forbids the Accessibility control a tiler needs.

The spatial model

• A workspace is a row; an app window is a cell in it. New windows go to the end of the row, new workspaces below.
• Up/down changes workspace, left/right changes window. The screen is a viewport onto a larger grid that stays sorted.
• One address: every managed window lives in exactly one workspace on exactly one display.
• Down always leads somewhere: every display's stack ends in one empty workspace.
• Per-display rails: every display has its own stack, and a whole workspace can move between displays (Fn+⌥⇧+arrows).
• Categories are identity: the rail shows what each row is (web, terminal, coding, media) instead of asking you to name it.

Live capture.

Placement memory

• Windows go back to their workspace and display across restarts; displays are matched by UUID, not arrangement order.
• Category routing: with category-order, each category gets its own row at the top of every display, so a new browser window lands with the other browsers.
• The launch-crowd rule: an app that restores a pile of windows at login gets its own row instead of flooding yours.
• No invisible windows: every window the shell lists can be reached with one click or command, and parked windows are recovered after a crash.

Live capture.

The tiling engine

Windows are always tiled and never overlap. Fn+Space cycles maximize, split (an N-column sliding view, N per workspace), column, half and grid.

Live capture.

• Layouts are data: draw your own in the layout editor, or write [[layout]] blocks in config.toml.
• Resize, one model for every layout: drag a border, or Fn+⌃A/D/W/S in 5% steps that stop on 25/50/75%; Fn+⌃= balances. Sizes are kept per workspace and per layout.
• A minimum-size floor with paging: no window gets less than 120 × 80 pt; overflow pages, and the parked windows keep their tabs.
• The reconciler owns geometry: one pure function decides where every window goes, and every click re-enters the same command pipeline as a hotkey.

Design

No colour palette of its own: native vibrancy materials, your system accent colour, light and dark from System Settings. Two panels, one job — showing you where you are:

• The rail (left): one row per workspace with its apps and category, hover previews, a tray for hidden and minimized windows, right-click menus, scroll to switch, and Dock-style auto-hide.
• The tab bar (top): one tab per window, drag to reorder or onto a rail row to move it, right-click for Close / Float / Move to workspace, middle-click to close.

Live capture.

Hold Fn for a cheat sheet of your bindings, Fn+Tab for the overview, Fn+Esc for Zen mode. Reduce Motion is respected.

A keyboard grammar

The Fn / Globe key takes the place of Super; a ⌃⌥ preset covers keyboards that never send Fn.

Modifier	Meaning	Examples
Fn	navigate	Fn+W/S rows, Fn+A/D windows, Fn+1…0 workspace N
+ ⇧	move the window	Fn+⇧A/D along the row, Fn+⇧W/S between rows, Fn+⇧+arrows to a display
+ ⌃	resize	Fn+⌃A/D narrower/wider, Fn+⌃W/S shorter/taller, Fn+⌃= balance
+ ⌥	display / whole app	Fn+⌥W/A/S/D focus a display, Fn+⌥1…9 tab N, Fn+⌥⇧+arrows move the workspace

Every chord can be rebound — see Keybindings. Scripts drive the shell through spacialctl (control socket).

Get started

brew install --cask askalice/tools/spacialshell

Or download the notarised DMG from Releases, move it to /Applications, launch it and grant Accessibility. Grant Screen Recording too for hover previews and sliding switches; without it switches are instant and everything else works.

Then press Fn+S.

Credits

SpacialShell exists because of material-shell (material-shell.com) and Veshell, by PapyElGringo and the Free Explorers collective. It borrows their design — the model, the vocabulary, the "not-desktop" — and no code; like both, SpacialShell is GPL-3.0. The macOS platform layer adapts MIT-licensed code from AeroSpace.