In simple English
This program helps you test how computer systems talk to each other. You type in a web address and send data to see what comes back. It runs on your own computer and keeps your data private. It costs nothing for personal use, but requires a paid licence for work use. You can download it directly to your desktop without using complicated commands.
What it is
Yaak is a desktop API client (a program with buttons and text boxes for sending web requests and reading server replies) built with Tauri (a framework for making desktop apps with web technologies), Rust (a programming language known for speed and safety), and React (a JavaScript library for building user interfaces). It lets you send REST, GraphQL, gRPC, WebSocket, and Server-Sent Events requests.
What it is good for
Solo builders who want to test their web backends, talk to payment providers, or check database endpoints without slow, heavy software.
- Runs completely offline and keeps your data on your machine.
- Supports modern protocols like gRPC and WebSockets alongside standard REST.
- Saves files directly to your computer folder so you can track them in Git (a system for tracking changes in code).
- Prebuilt binaries require a paid licence for commercial use, despite the MIT licence on the source code.
- New feature contributions from the community are restricted.
- Desktop app needs several hundred megabytes of RAM while running.
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Download Yaak for macOS, Windows, or Linux directly from yaak.app/download.