# Vayu

> Open source desktop app for REST and GraphQL API testing and load testing. Local-first, no account required, no cloud sync.

Vayu is a free Postman alternative that runs entirely on your machine. It combines a familiar request-builder UI (Electron + React) with a high-performance C++ execution engine that can sustain tens of thousands of HTTP requests per second for load testing.

## Key facts

- **Platforms**: Windows (x64), macOS (universal), Linux (AppImage)
- **License**: Engine - AGPL-3.0 / UI - Apache-2.0
- **No account, no telemetry, 100% offline**
- **Import formats**: Postman v2.0/v2.1, Insomnia v4, OpenAPI 3.0, Swagger 2.0
- **Scripting**: QuickJS with `pm.*` API - compatible with Postman test scripts
- **Auth**: Bearer, Basic, API key, and OAuth 2.0 (client credentials, password, authorization code + PKCE); resolved engine-side
- **Load testing**: built-in, real-time metrics streaming via SSE
- **Variable resolution**: layered - globals → collection chain → active environment

## Architecture

Sidecar pattern: Electron UI (Manager) communicates with a C++20 daemon (Engine) over HTTP on localhost:9876. The separation keeps the UI responsive during high-throughput load tests.

## Documentation

Documentation site: https://athrvk.github.io/vayu/

- [README](https://github.com/athrvk/vayu/blob/master/README.md)
- [Architecture](https://athrvk.github.io/vayu/architecture/)
- [Engine API Reference](https://athrvk.github.io/vayu/engine/api-reference/)
- [Engine Scripting](https://athrvk.github.io/vayu/engine/scripting/)
- [MCP Server](https://athrvk.github.io/vayu/engine/mcp/)
- [Variable Resolution](https://athrvk.github.io/vayu/app/variable-resolution/)
- [DB Schema](https://athrvk.github.io/vayu/engine/db-schema/)
- [Building](https://athrvk.github.io/vayu/building/)

## Download

https://github.com/athrvk/vayu/releases/latest
