MiniSnip

A lightweight, privacy-friendly Windows screenshot tool that copies exactly what you need.

MiniSnip is a minimal Windows screenshot utility that sends captures directly to the clipboard. It stays quietly in the background, waits for the global Alt + W shortcut, and opens a lightweight overlay on top of a frozen desktop image.

There is no telemetry, no account, and no network service. Your screenshots stay local and are copied directly to the Windows clipboard.

Features

• Press Alt + W to open the capture overlay.
• Drag to copy a rectangular region.
• Hold Shift while dragging to constrain the selection to a square 1:1 ratio.
• Hover a visible window to display a subtle orange outline.
• Click a highlighted window to copy its exact bounds.
• Press Esc to close the overlay without changing the clipboard.
• Run a single MiniSnip instance at a time.
• Keep Win32 window coordinates aligned with screenshot pixels through DPI awareness.

Quick Start

Download a release

Download mini_snip.exe from the latest release, place it anywhere you like, and run it. The executable is self-contained and does not require a system-wide installation.

The published executable is not digitally signed, so Windows may display a warning the first time you start it. The full source and build scripts remain available in this repository for auditing and local builds.

Build from source

Clone the repository and run the installation script from PowerShell:

git clone https://github.com/Mirochill/MiniSnip.git
cd MiniSnip
.\install.ps1

The script builds the application, runs the tests, copies the executable to %LOCALAPPDATA%\Programs\MiniSnip, and starts MiniSnip in the background.

To start MiniSnip manually later:

& "$env:LOCALAPPDATA\Programs\MiniSnip\mini_snip.exe"

To remove the local installation:

Get-Process -Name mini_snip -ErrorAction SilentlyContinue | Stop-Process
Remove-Item "$env:LOCALAPPDATA\Programs\MiniSnip" -Recurse -Force

Usage

Action	Result
Alt + W	Open the capture overlay
Drag	Copy a rectangular region
Shift + drag	Copy a square 1:1 region
Hover a window	Highlight the detected window
Click a highlighted window	Copy the complete window
Esc	Close the overlay without touching the clipboard

Requirements

• Windows 10 or Windows 11.
• Windows PowerShell 5.1 or PowerShell 7.
• .NET Framework 4.x with C:\Windows\Microsoft.NET\Framework64\v4.0.30319\csc.exe.
• No additional SDK, NuGet package, or third-party dependency.

Build and Test

MiniSnip intentionally uses the .NET Framework compiler already available on Windows. The project stays easy to audit and quick to build:

.\build.ps1
.\test.ps1

The test script compiles a temporary executable, runs the checks, and removes the temporary artifact. The current suite covers:

• rectangular selection normalization;
• square Shift 1:1 selection and screen boundaries;
• topmost visible window priority;
• the absence of a target outside detected windows;
• overlay construction on the current desktop.

GitHub Actions runs build.ps1 and test.ps1 on windows-latest.

Design

MiniSnip avoids an active monitoring loop. Windows notifies the application when Alt + W is pressed. Visible windows are enumerated and the desktop image is copied only when the overlay opens.

During interaction, MiniSnip invalidates only the regions that visually change. The opaque screenshot buffer uses a 24-bit RGB format, and reusable graphics resources stay cached for the lifetime of the overlay.

The measurement method and before-and-after results are documented in docs/PERFORMANCE.md.

sequenceDiagram
    participant U as User
    participant W as Windows
    participant M as MiniSnip
    participant C as Clipboard

    U->>W: Alt + W
    W->>M: WM_HOTKEY
    M->>M: Capture desktop and detect windows
    M-->>U: Display overlay
    U->>M: Click or drag
    M->>C: Copy selected image
    M-->>U: Close overlay

Loading

Repository Layout

Path	Purpose
src/	WinForms source code and Win32 interop
tests/	Self-contained tests without third-party dependencies
build.ps1	Optimized compilation of mini_snip.exe
test.ps1	Test compilation and execution
install.ps1	Local build, verification, installation, and startup
app.manifest	Windows compatibility and asInvoker privilege level

Contributing

Focused fixes and measurable improvements are welcome. Read CONTRIBUTING.md before opening a pull request. All participation in this project must follow the Code of Conduct.

To report a vulnerability, follow SECURITY.md instead of opening a public issue.

License

MiniSnip is available under the MIT License.