Good tools, freely given.

Open source and free. Pixel art, music, documents, your files and a place to share them, in your browser and on your desktop, at no cost.

Open Sprite Open Box Download

AsteriaSprite

Layers, frames and onion skin. Shading and dither brushes, outlines, rotation that keeps pixels clean. Sheets for Godot, GIFs for everyone else.

Describe a sprite and the assistant draws it with the same tools you use, one step you can undo at a time.

Open in your browser More about Sprite

lantern.asprite.json

AsteriaBox

Chiptune or a whole band: guitars, bass, organ, strings, choir and a real drum kit. Power-chord riffs, a mix that balances itself, and MP3s ready to share.

Built on BeepBox. Every song on this page was written with it.

Open in your browser More about Box

first-light.beepbox

The soundtrack

Freely Given

Eight tracks · Asteria Technology · 2026

First Light

Your files, together.

Asteria Cloud

3 GB for every Asteria account. Sprite, Box and Office save there, and your computer stays in sync.

Open Cloud

Asteria Office

Documents, spreadsheets, presentations and PDFs. Write together in the browser, or on your desktop.

Open Office

Learn to build it.

Swift: Zero to Hero

From your first line of Swift to apps for iPhone, iPad and Mac on the App Store. Write real code in your browser, with tests that check it as you go.

Start learning

Yours to keep.

Every line, open

Sprite, Box, Social and this site are published in full under the Asteria License, which is the GNU GPL, version 3. Read it, change it, share it.

The source

Run here, or anywhere

The apps run on our servers at no cost to you, install from the browser, or download for macOS, Windows and Linux. They work offline.

Downloads

Your work stays yours

No account and no tracking. Files stay on your device. The assistant uses your own key and talks only to Anthropic.

How it works