The platform

Everything an app needs, already on the machine.

Egg is the client-side backend your cloud has been missing. You build against one SDK, and the platform provides the rest on the user's own device, then helps your app reach them in any browser.

What you get

One SDK. The whole backend.

AI, any model

Text, vision, audio, and video through one surface, speaking the Prompt API and OpenAI shapes. Routed to a local model or the user's own provider. You don't choose or pay for the model; they do.

Data that stays put

Local SQL your app owns, with optional end-to-end-encrypted sync across the user's own devices. The cloud, if it's involved at all, only ever sees ciphertext.

The user's own logins

A credential vault and the sessions the user is already signed into, brokered to your app by explicit grant. Reach sites as the real, logged-in user, not a blocked scraper.

Agents and tools

A local agent runtime your app can call, and tools your app exposes that the user's agent can call back. Composition between apps with no server in the middle.

What you can build

Five things a normal browser can't.

Run AI with no API key

A page calls a capable model that's the user's own, local or their provider, billed to no one. A normal browser can't hand a page a model.

Act as the signed-in user

Read and fetch from the sites they're already logged into, by permission, as the real user. A normal browser walls every origin off from every other.

Keep data on the device, synced

Own local SQL that persists and rides end-to-end-encrypted sync across the user's machines. A normal browser offers sandboxed storage and no cross-device sync.

Work while the window is closed

Schedule background jobs that keep running with no tab open, because the engine outlives the UI. A normal browser kills your page when the tab goes away.

Call a local agent

Invoke an on-device agent, and expose tools the user's agent and other apps can call back, with no server in the middle. A normal browser has none of this.

Distribution

Ship a web app. It runs where your users already are.

An Egg app is just a web bundle. Host it anywhere; it runs in the browser your users already have, or in Egg. Publish to the gallery and they add it in a click. Egg is a free install that ships with its own apps, so there's an audience on day one. No browser-switching required.

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