Introduction

Native SDK is an open source toolkit for building beautiful native desktop applications. It combines markup for declarative interfaces, a predictable message-based state model, a modern component library, a native renderer, and tooling for building, running, and packaging apps — one codebase for macOS, Linux, and Windows, with experimental iOS and Android support riding the same runtime.

It exists because expressive UI and native performance should not be competing goals. Developers often choose web-based runtimes because they offer freedom, speed and control over the product experience. But that freedom often comes with a heavy runtime. Native SDK keeps the expressive authoring model and replaces the runtime with native rendering.

Six principles guide every decision in the toolkit.

Beautiful by default

Great software should not start from a blank slate. The built-in components ship with considered typography, spacing, and color, and native init scaffolds an app that already looks intentional the first time its window opens. The example apps in the repository are held to the same bar: design excellence is a reason Native SDK exists, not an afterthought.

Customizable by design

Your app should have its own identity, not ours. Styling is design tokens end to end: color, radius, and typography resolve by name, re-resolve live when the theme changes, and can be replaced wholesale. The defaults are a starting point, never a look you are locked into.

Native from the start

Every interface is rendered without a browser or WebView. Native SDK draws its own pixels through its own engine into real OS windows, and the parts users touch stay with the operating system: scroll physics, menus, dialogs, the tray, text input, HiDPI. See Native UI and Platform Support. When part of your product genuinely is the web, WebViews coexist with the native canvas — by choice, not by default.

Predictable state

State changes should be explicit, inspectable and easy to reason about. Events produce messages, messages update state, and state renders the interface. There is exactly one place state changes — the update function — which makes an app simple to debug, simple to test headless, and simple to maintain. The App Model walks the loop end to end.

Simple authoring

Interfaces should be easy to read, easy to write and easy to generate. Views are declarative markup with bindings and message dispatch — no lifecycle, no hidden state, no imperative wiring — validated at check and compile time with teaching errors that point at a line and column. Native UI covers every element and pattern.

AI is part of the workflow

Native SDK is designed for a world where humans and AI agents build software together. The properties that make apps easy for people to reason about — declarative views, one typed update function, explicit state — are the same ones that make them reliable for agents to generate. Every app can embed an automation server so any agent can see and drive the running window: snapshots, assertions, input, screenshots.

Where to go next

Ready to build? The Quick Start takes you from install to a running, tested app, the CLI covers every verb the tooling provides, and Config documents the app.zon manifest.