A strip that runs past your screen
Grid tilers squeeze every new window into the space that's already there. Monorail does the opposite.
Open a window
It slides in beside the one you're using. Everything else keeps its size.
Move along
⌃⌥← →, the mouse wheel, a swipe or the slider: the strip glides just far enough.
See it all
⌃⌥O zooms out to every workspace and slide. Drag windows anywhere.
Drop a window where you want it
Drag a window onto another one. Near an edge it docks beside it; in the middle the two become a tab group. Any apps, as deep as you like. Try it here.
Drag onto an edge of any window. A highlight shows the half it will take; let go and it docks there.
Keep going. Dock onto a docked window and that half splits again, as deep as you like.
Drop in the middle for a tab group, even across apps. Drag a tab out to tear it off.
Drag the gap between two windows to resize both at once.
Undock with ⌃⌥⇧] for a slide of its own, ⌃⌥T to float (here, drag to Floating), or ⌃⌥Z to undo.
Calm to use, powerful when you need it
Over 250 actions, all in the command palette and all free. Here are the ones people love first.
Say it ⌃⌥/
“Slack and Mail side by side on 3.” “Safari two thirds.” “How do I keep my Mac awake?” Understood on your Mac.
Smart slides
Windows of one app share a slide. Pair any two, in grids, main + side, tabs or tall slides.
Overview ⌃⌥O
Every workspace on one colourful canvas. Drag to pair, reorder, move or close.
Stay Awake
For an hour, while downloading, or by itself when a trigger applies. Even with the lid closed, safely: it stops if the Mac gets hot or runs on battery.
Evening Mode
Less blue light at night, as warm as you like with a slider. On by hand or every evening, fading in gently.
AI agent alerts
A chime when Claude Code or Codex waits for approval. Assistants can drive Monorail over MCP.
Safe screen sharing
Private windows step aside the moment you share in Zoom, Teams or Meet.
Focus and deep work ⌃⌥B
Dim everything but your slide, hide distracting apps, pomodoro in the menu bar.
Displays that remember
Unplug and replug: every window goes back where it was. A layout for each desk.
No chords needed
Tap right ⌥ for slide mode, or use Vim keys, a MIDI pad, a game controller or your phone.
Dock anything, nest anywhere
Drag a window onto another's edge to dock it beside, or onto its middle for a tab group, any apps, as deep as you like. Drag the gap to resize both.
Saved views ⌃⌥⌘1
Nine places per display to jump back to, plus back and forward through where you've been, like a browser.
Draw your own layouts
The zone editor splits a slide any way you like. Use it on any slide from its menu.
Switch in a minute
Imports your shortcuts, gaps and app rules from AeroSpace, yabai and skhd, or Rectangle.
Tags
Keep a window on the workspaces you choose, or show another workspace alongside this one.
Built to be scripted
monorail:// links, a CLI with a live event stream, a local API, MCP for AI assistants, and shareable layout links.
Five keys and you're flying
Every shortcut starts with ⌃⌥ (or Caps Lock, if you like). Try them right here: this page listens.
| Slide left and right | ⌃ ⌥ ← → |
| Move the window along | ⌃ ⌥ ⇧ ← → |
| Cycle widths | ⌃ ⌥ R |
| Full width | ⌃ ⌥ F |
| Overview | ⌃ ⌥ O |
| Command palette | ⌃ ⌥ / |
| Workspaces | ⌃ ⌥ 1…9 |
| Undo | ⌃ ⌥ Z |
All 226 actions: the full list.
Practice pad
- ✓Slide left: ⌃⌥←
- ✓Slide right: ⌃⌥→
- ✓Cycle the width: ⌃⌥R
- ✓Full width: ⌃⌥F
- ✓Open the overview: ⌃⌥O
Press them anywhere on this page. The demo above follows along.
27 themes, including one that follows the seasons
Pick one. The overview, the slider and every workspace dot change with it.
So light you'll forget it's running
Measured on a 14-core MacBook Pro, on battery, while idle. Settings → About → Check Energy measures it on yours.
Your windows stay yours
Your windows, titles and apps never leave your Mac. Monorail sends only anonymous daily counts (version, Mac model, features on), and you can turn that off.
Accessibility, so it can arrange windows. Others only when you turn a feature on.
Sentences, predictions and suggestions run locally. No cloud AI.
Every line is public under the Functional Source License. Read it, build it, check what it does.
Everything others do, without the squeeze
Grid tilers shrink every window to fit one more. Snapping tools leave you arranging by hand. Monorail does neither.
| Monorail | Grid tilers | Snapping tools | |
|---|---|---|---|
| New windows keep everyone's size | ✅ | ❌ squeezes the rest | ✅ |
| Unlimited windows per screen | ✅ on a strip | ❌ ever-smaller tiles | ❌ they overlap |
| Drag onto a window to dock or tab it, any apps | ✅ | partly | ❌ |
| Saved views, back and forward | ✅ | ❌ | ❌ |
| Understands plain sentences | ✅ on device | ❌ | ❌ |
| Knows when an AI agent needs you | ✅ | ❌ | ❌ |
| Keeps private windows out of screen shares | ✅ | ❌ | ❌ |
| Imports your old setup | ✅ | ❌ | ❌ |
| Every feature free, no window limits | ✅ | varies | mostly paid |
On the Mac today. Windows and Linux are coming.
The same strip, the same docking and the same shortcuts, made natively for each system.
macOS
macOS 13 or later, on Apple silicon and Intel. Free, with every feature.
Download for Mac →Windows
For Windows 11 and 10: one strip across your screens, drag-to-dock, saved views and the command palette.
I want it on Windows →Linux
For GNOME and KDE on Wayland and X11, with the same keyboard-first design.
I want it on Linux →Star or watch the repository to hear when they're ready.
Good questions
Is it really free?
Yes. No trial, no subscription. The source is on GitHub under the Functional Source License.
Is it safe to install?
Yes. Every release is signed with Ashforde's Apple Developer ID and notarised by Apple, so macOS opens it without warnings. It's built in public on GitHub from the source you can read, checked by CI on every change, and every download has a published SHA-256 checksum.
Will it fight my other window tools?
Turn off other tilers' snapping and Stage Manager; Settings → General → Mac setup checks for you.
What happens to my windows if I quit?
Every window comes back on screen. Next time Monorail starts, your layout returns.
Does it work with multiple displays, projectors and Sidecar?
Yes: each display gets its own strip, an unplugged display's windows come back when you reconnect, and Sidecar iPads fit every slide.
Which languages?
English, German, French, Spanish, Japanese, Chinese (Simplified), Portuguese, Korean and Italian.
I use AeroSpace, yabai or Rectangle. Can I bring my setup?
Yes. Settings → Basics → Import Settings… brings over your shortcuts, gaps, floating apps and workspace rules.
Is there a Windows or Linux version?
Not yet. Both are on the way, with the same strip, docking and shortcuts. Tell us which you'd use from the section above, and watch the repository to hear when they're ready.
Is anything behind a paywall?
No. Docking, nesting, tab groups, saved views, URL commands and every display are free, with no window limits.
Can I script it?
monorail:// links, a command-line tool, a local API, an MCP server for AI assistants, AppleScript and JavaScript scripts with a gallery.
Give every window room.
Download Monorail, allow Accessibility, and you're sliding in under a minute.
brew tap ashfordeOU/monorail https://github.com/ashfordeOU/monorail && brew install --cask monorail