Chroma-Fs

Chroma-Fs (@chroma/fs) is a sibling JavaScript library in the Chroma ecosystem. It gives apps a single storage API that automatically picks the right backend:

• Static apps (browser) → IndexedDB by default
• Dynamic apps in Chroma Desktop → real filesystem under per-app data directories
• Dynamic apps in a plain browser → IndexedDB unless you force filesystem in config (which requires a Tauri host)

Chroma-Fs is not a Chroma engine plugin. Apps import it as an npm package and configure it with chroma-fs.json.

Quick start

# Recommended: standard template with Chroma-Fs demo
chroma new my-app --template standard
cd my-app && chroma dev

# Or add storage to an existing app
chroma fs init          # creates chroma-fs.json with template defaults
chroma fs link          # links @chroma/fs from the workspace (monorepo dev)

import { createChromaFs } from "@chroma/fs";

const fs = await createChromaFs({ configPath: "./chroma-fs.json" });
await fs.writeFile("notes/todo.txt", "Buy milk");
const text = await fs.readText("notes/todo.txt");

Where data lives

On desktop, apps run inside an iframe without direct Tauri access. Chroma Desktop bridges filesystem calls via postMessage — see Backends.

Related

• Templates — standard template with file explorer demo
• CLI — chroma fs init, chroma fs link, dynamic develop mode
• Desktop — iframe hosting and develop mode
• Configuration — chroma-fs.json schema
• API — full method reference