libghostty-dotnet
March 31, 2026 · View on GitHub
.NET examples and interop bindings for libghostty windows soft fork.
This repo also serves as a visual testing ground: an automated test suite launches each example, sends input, resizes windows, runs commands, and verifies correct rendering across DPI modes using screenshot comparison.
Prerequisites
- Zig (0.15+): builds libghostty from source
- .NET SDK 9.0: builds and runs examples
- ClangSharp: regenerates bindings when the C API changes
Install on Windows
# winget
winget install zig.zig
winget install Microsoft.DotNet.SDK.9
# or choco
choco install zig dotnet-sdk
# ClangSharp (dotnet global tool)
dotnet tool install --global ClangSharpPInvokeGenerator
Setup
./setup.ps1
This clones and builds libghostty from source, then restores .NET packages.
After setup, open any example .slnx in Visual Studio or run with dotnet run.
Examples
| Example | Description | Status |
|---|---|---|
| Win32 | Raw Win32 P/Invoke, direct port of the C example | Done |
| WinForms | Panel-based embedding with WinForms events | Done |
| WPF-Simple | HwndHost embedding with GhosttyApp wrapper | Done |
| WPF-Direct | HwndHost embedding with raw NativeMethods | Done |
| WinUI 3 | SwapChainPanel composition surface (#3) | Done |
| Unity | In-game terminal via render texture | Planned |
| Avalonia | Cross-platform NativeControlHost | Planned |
Visual Testing
The test suite uses FlaUI for UI automation and ImageSharp for screenshot comparison.
Test coverage
| Feature | Tested | Notes |
|---|---|---|
| App launch | ✅ | Window appears within timeout |
| Window title | ✅ | Not empty |
| Window size | ✅ | Valid dimensions, reasonable bounds |
| Terminal renders | ✅ | Screenshot is not blank |
| Clean shutdown | ✅ | WM_CLOSE, exit code 0, no crash dialog |
| Keyboard input (typing) | ✅ | Visible output after keystrokes |
| Enter executes command | ✅ | Screen changes after Enter |
| Backspace | ✅ | Visible change after deleting characters |
| Window resize | ✅ | Terminal updates, two sizes compared |
| Minimum window size | ✅ | Shrink to 320x240, no crash |
| Focus/cursor | ✅ | Cursor visible when focused |
| Command execution | ✅ | echo output, prompt returns |
| Scrollback | ✅ | Shift+PageUp after generating output |
| Clipboard copy/paste | ✅ | Select, copy, type, paste cycle |
| Long-running commands | ✅ | Output updates over time (ping) |
| DPI: Unaware mode | ✅ | Launches and renders |
| DPI: SystemAware mode | ✅ | Launches and renders |
| DPI: PerMonitorV2 mode | ✅ | Launches and renders |
| DPI: mode affects rendering | ✅ | Screenshots differ across modes (high-DPI displays) |
| DPI: window reports value | ✅ | GetDpiForWindow >= 96 |
| Unicode/emoji input | ❌🔨 | |
| Mouse click | ❌🔨 | SendMouseButton API exists |
| Mouse selection (drag) | ❌🔨 | |
| Mouse scroll (wheel) | ❌🔨 | SendMouseScroll API exists |
| Ctrl+C (interrupt) | ❌🔨 | |
| Tab completion | ❌🔨 | |
| ANSI colors/formatting | ❌🔨 | Verify colored output renders differently |
| Cursor styles | ❌🔨 | Block, beam, underline |
| Window maximize/restore | ❌🔨 | |
| Window minimize/restore | ❌🔨 | |
| Multi-monitor (move between) | ❌🔨 | DPI change on move |
| Fullscreen toggle | ❌🔨 | |
| Content scale changes | ❌🔨 | SetContentScale API exists |
| Occlusion handling | ❌🔨 | SetOcclusion API exists |
| Modifier keys (Ctrl, Alt, Shift) | ❌🔨 | Key combos beyond clipboard |
| Rapid input (stress) | ❌🔨 | Fast typing, no dropped keys |
| Rapid resize (stress) | ❌🔨 | Continuous resize, no crash |
| Resource cleanup | ❌🔨 | No handle/memory leaks after close |
| Selection clipboard | ❌🔨 | supports_selection_clipboard in config |
| Surface close callback | ❌🔨 | Terminal-initiated close |
| Multiple surfaces | ❌🔨 | More than one terminal per app |
| Config loading | ❌🔨 | ghostty_config_load_default_files |
# Run all visual tests
just test-visual
# Smoke tests only (fast)
just ci-test-smoke
# Full CI pipeline (build + all tests)
just ci
# Update screenshot baselines after intentional visual changes
just update-baselines
Tests are parameterized across all examples. Adding a new example to TestConfiguration.AllExamples automatically includes it in every test.
On workstations, tests use aggressive focus management to handle other windows competing for foreground. In CI (CI env var set), focus handling is lightweight since no contention exists.
Updating libghostty
# Use custom repo/branch/commit
./setup.ps1 -Repo https://github.com/deblasis/ghostty.git -Branch windows -Commit abc123
# Save the override to libghostty.json
./setup.ps1 -Repo https://github.com/deblasis/ghostty.git -Branch windows -Commit abc123 -Save
Regenerating bindings
When the C API changes:
./generate-bindings.ps1
Requires ClangSharp: dotnet tool install --global ClangSharpPInvokeGenerator