15:I[981,["658","static/chunks/658-a698693f56d0116a.js","183","static/chunks/183-6beeeb801c274aaa.js","474","static/chunks/app/%5Btype%5D/layout-631c4730b83c8223.js"],"Posts"] 16:T59c,Hi HN,

I built Vayu because I was frustrated with the current state of API tools. Postman has become bloated and forces cloud sync, while high-performance tools like JMeter or k6 often lack a decent GUI for quick debugging.

Vayu attempts to bridge that gap. It is an open-source, local-first API client (like Postman, Insomnia) that includes a high-performance load-testing engine (written in C++20) under the hood.

Key technical decisions: - Sidecar Architecture: The UI is Electron/React (for usability), but it spawns a separate C++ daemon ("The Engine") to handle actual networking. - This allows the UI to remain responsive even while the engine is pumping thousands of requests per second during a load test. - Privacy: It is 100% local. No cloud sync, no accounts required. - Scripting: Uses QuickJS for test scripts (compatible with the `pm.test` syntax you already know).

I have tested upto 60k rps locally on Macbook Pro M3

It is currently v0.1.1. I have builds for Windows, Linux, and macOS. (PS: macOS requires some extra steps to run via the dmg file, will have to find a workaround)

I am looking for feedback specifically on the "Engine" performance and the developer experience of the load-testing flow, and developers to help me improve the UI.

Repo: https://github.com/athrvk/vayu17:T41f,Hi HN,

I built a small invoice tool for an internal requirement at my company.

We work with several suppliers and providers and wanted to give them a simple way to create invoices directly inside our workflow. The goal was to increase operational visibility: track what’s been created, sent, viewed, and paid, without the need for an accounting system like Xero or QuickBooks if they do not have it.

I extracted

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