For module developers · schema 5.0

Build a module for the festival.

A module is one manifest, a sandboxed UI, and a permissioned bridge to the desktop. Build a small app, publish it to the Module Store, and it runs in every user's window. No prior experience assumed.

Build your first module New? Start here

19guides & references

29capabilities

100%sandboxed & safe

Ship your first module in four steps

Full walkthrough

01Scaffold

hanabi module init "My Module"

Starter manifest, a UI shell and a sample input.

02Validate

hanabi module validate ./my-module

The same rules the backend runs on upload.

03Package

hanabi module pack ./my-module

A safety-scanned, upload-ready zip.

04Publish

Developer Portal → New module

Upload, admin review, then the Module Store.

Capability bridge

The SDK, in four calls

Capability API

Your UI reaches the desktop only through declared, scoped capabilities — the SDK turns that protocol into plain await calls. Tap one:

module.ts

const hanabi = createHanabiClient();
const ctx = await hanabi.ready();
// → { user, theme, accent, windowId }

{ "user": "kana", "theme": "dark", "accent": "#ff5c8a" }

Platform pulse

What's new

Full changelog

The platform ships continuously. Here's the latest, plus where the roadmap stands.

v5.7.0

Desktop & filesystem module capabilities

Modules can now (with permission) integrate with the desktop workspace and manage the virtual filesystem beyond their own folder.

v5.7.0

In-portal module debugger

The Developer Portal now has a debug console that streams a running module's bridge requests and replies (including any error code) so yo…

v5.7.0

Capped DEV sandbox — test heavy modules before approval

A draft that declares a heavy capability (worker.native for the ffmpeg/imagemagick/libvips image, or network.fetch.broad for open-web fet…

Roadmap Foundations Capability bridge Worker sandbox Module Store Streaming You are here

One manifest. A sandboxed UI. A permissioned bridge.

Your UI runs in an opaque-origin iframe and reaches the platform only through the capability bridge — every call declared, granted, and scoped. The SDK turns that protocol into plain await calls.

files.readfiles.writedata.storejobs.createnotifications

import { createHanabiClient } from '@hanabi/module-sdk';

const hanabi = createHanabiClient();
const ctx    = await hanabi.ready();               // read context

const { files } = await hanabi.pickFile(['xlsx']); // files.read
const file = await hanabi.readFile(files[0].id);   // file.bytesB64

await hanabi.writeFile('result.csv', out);         // files.write