Install

One entry point, zero runtime dependencies. Backed by IndexedDB; runs in any browser with a working IDB implementation (Chromium, Firefox, WebKit).

The library will not run in Node — it does not fake persistence with an in-memory shim. If your application boots in an SSR context, guard the createDurable() call behind typeof window !== "undefined" and open slots after hydration.

Probe the runtime before you commit valuable state:

import { createDurable } from "@0xsarwagya/durable-local";
 
const durable = createDurable();
const status = await durable.storage();
 
// {
//   persistent: false,
//   quotaBytes: 12897234432,
//   usageBytes: 45120,
//   quotaRounded: false,
//   privateMode: "no",
//   evictionRisk: "best-effort",
//   engine: "chromium",
//   installedWebApp: false
// }

evictionRisk tells you the honest truth:

• session — Chrome Incognito / Firefox Private / Safari Private. Wiped at session end.
• ephemeral — persist denied or heuristic best-effort. Browser may evict under pressure.
• best-effort — default storage box. Not persisted, not necessarily evicted.
• persistent — the browser considers this origin protected from automatic eviction.
• ios-capped — Safari regular tab with persist()=true. Sounds persistent; ITP still evicts after 7 days of no interaction. Ask the user to install as a Home Screen web app.

Call durable.requestPersistence() after the user does something that proves the value matters. See durability.