twm - Auto-Tiling Window Manager for Windows

A lightweight auto-tiling window manager for Windows 10/11. No keyboard shortcuts to learn — just run it and your windows automatically tile.

How It Works

1. Run twm.exe
2. Open windows normally (browser, editor, terminal, etc.)
3. Windows are automatically arranged in a tiling layout — no overlap, no gaps
4. Close a window and the remaining windows automatically re-tile to fill the space

That's it. No shortcuts to memorize, no configuration required.

┌─────────────┬─────────────┐     ┌───────────┬───────────┐
│             │             │     │           │           │
│   Browser   │   Editor    │ ──→ │  Browser  │  Editor   │
│             │             │     │           ├───────────┤
│             │             │     │           │ Terminal  │
└─────────────┴─────────────┘     └───────────┴───────────┘
     2 windows                          3 windows

Multi-Monitor

When multiple monitors are detected, windows are automatically distributed evenly across monitors — approximately 2 windows per monitor before any monitor gets a 3rd.

  Monitor 1                Monitor 2
┌──────┬──────┐       ┌──────┬──────┐
│      │      │       │      │      │
│ Win1 │ Win2 │       │ Win3 │ Win4 │
│      │      │       │      │      │
└──────┴──────┘       └──────┴──────┘

Dragging a window to another monitor is detected and the layout is automatically updated.

Features

• Zero configuration - Just run the exe, windows auto-tile
• BSP layout - Binary Space Partitioning for balanced splits
• Multi-monitor balanced distribution - Windows spread evenly (~2 per monitor)
• DPI-aware - Correct positioning on high-DPI displays
• DWM border compensation - Pixel-perfect tiling
• Lightweight - ~1.1MB binary, event-driven, near-zero CPU at idle
• No shortcuts - No keyboard hooks, no conflicts with other apps

Installation

Download

1. Download twm.exe from the Releases page
2. Run twm.exe

Auto-start at login: Press Win+R, type shell:startup, place a shortcut to twm.exe there.

Run as Administrator for managing elevated windows (e.g., Task Manager).

Build from source

# Install Rust (https://rustup.rs)
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

# Clone and build
git clone https://github.com/kimkimjp/twm.git
cd twm
cargo build --release

# Cross-compile from Linux
rustup target add x86_64-pc-windows-gnu
sudo apt install mingw-w64
cargo build --release --target x86_64-pc-windows-gnu

Configuration

Optional config file: %APPDATA%\twm\config.yaml

gaps:
  inner: 5    # Gap between windows (pixels)
  outer: 10   # Gap between windows and screen edge (pixels)

window_rules:
  - class: "TaskManagerWindow"
    command: "floating"
  - title: "Calculator"
    command: "floating"

If no config file exists, twm uses sensible defaults (5px inner gap, 10px outer gap).

Uninstallation

1. Close twm.exe (end task from Task Manager)
2. Delete twm.exe
3. Remove the shortcut from shell:startup (if configured)
4. Delete %APPDATA%\twm\ (optional, removes config)

No registry entries. No system files modified.

Architecture

twm.exe (single process, event-driven)
  |
  +-- Event Listener (SetWinEventHook + WINEVENT_OUTOFCONTEXT)
  |     Detects: window show, window destroy
  |
  +-- Window Manager Core
  |     +-- Monitor[] (auto-detected via EnumDisplayMonitors)
  |           +-- BSP Tree (auto-tiling layout engine)
  |
  +-- Win32 API Layer (DPI-aware, DWM border compensation)

Requirements

• Windows 10 or later
• No runtime dependencies

License

MIT