Greg.KeySub

A lightweight Windows utility that globally intercepts the § (section sign) key and replaces it with the backtick ` character.

Why?

On many European keyboards (including Italian), the backtick character is difficult to access, while the § key is readily available. This tool is especially useful for developers who frequently use backticks for:

• Markdown code blocks
• JavaScript template literals
• Shell commands
• And more...

Features

• System tray application - Runs silently in the background
• Global key interception - Works in any application
• Toggle on/off - Double-click the tray icon or use the context menu
• Start with Windows - Optional auto-start on login
• Keyboard layout detection - Automatically detects which key produces § on your keyboard

Installation

Option 1: Download Release

Download the latest version from the Releases page. Two versions are available:

File	Size	Requirements
Greg.KeySub-SelfContained.exe	~49 MB	None - includes .NET runtime, runs on any Windows 10/11
Greg.KeySub-FrameworkDependent.exe	~676 KB	Requires .NET 10 Runtime installed

Recommended: Use the Self-Contained version for maximum compatibility. Use the Framework-Dependent version if you already have .NET 10 installed and want a smaller download.

Option 2: Build from Source

# Clone the repository
git clone https://github.com/yourusername/Greg.KeySub.git
cd Greg.KeySub

# Build self-contained (larger, no dependencies)
dotnet publish src/Greg.KeySub -c Release -r win-x64 --self-contained -p:PublishSingleFile=true -o ./publish

# Or build framework-dependent (smaller, requires .NET 10)
dotnet publish src/Greg.KeySub -c Release -r win-x64 --no-self-contained -p:PublishSingleFile=true -p:EnableCompressionInSingleFile=false -o ./publish

Usage

1. Run Greg.KeySub.exe
2. The application appears in the system tray
3. Press § (or Shift+ù on Italian keyboards) to type ` instead

Tray Menu Options

• Enabled - Toggle key substitution on/off
• Start with Windows - Enable/disable auto-start on login
• Diagnostics - View detected keyboard layout information
• About - Application information
• Exit - Close the application

Requirements

• Windows 10/11
• .NET 10.0 Runtime (included in self-contained builds)

Building

# Restore and build
dotnet build

# Run tests
dotnet test

# Publish single-file executable
dotnet publish src/Greg.KeySub -c Release -r win-x64 --self-contained -p:PublishSingleFile=true

Project Structure

Greg.KeySub/
├── src/
│   └── Greg.KeySub/           # Main application
│       ├── Program.cs
│       ├── GlobalKeyboardHook.cs
│       └── TrayApplicationContext.cs
├── tests/
│   └── Greg.KeySub.Tests/     # Unit tests (NUnit)
└── Greg.KeySub.sln

How It Works

The application uses a low-level Windows keyboard hook (WH_KEYBOARD_LL) to intercept keystrokes globally. When the § character is detected:

1. The original keystroke is blocked
2. A backtick character is injected using SendInput

The hook runs efficiently by pre-detecting which virtual key codes produce § on startup, avoiding expensive character translation on every keystroke.

License

MIT License - See LICENSE for details.

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.