# @jsonjoy.com/fs-fsa

> File System Access API implementation backed by core filesystem primitives

Latest version **4.79.0** (published 2026-09-22) · Apache-2.0 license · 0 weekly downloads

## Install

```sh
npm install @jsonjoy.com/fs-fsa
pnpm add @jsonjoy.com/fs-fsa
yarn add @jsonjoy.com/fs-fsa
bun add @jsonjoy.com/fs-fsa
```

## Health

**Score 70/100 (B)** — status: active.

Positive: has types; no vulnerabilities; has provenance; recently updated; high maintenance score; high quality score.

Warnings: low downloads; no esm support.

## Facts

| | |
|---|---|
| Version | 4.79.0 |
| Published | 2026-09-22 |
| First published | 2026-01-19 |
| Weekly downloads | 0 |
| License | Apache-2.0 |
| TypeScript types | bundled |
| Module format | CommonJS |
| Node | >=10.0 |
| Dependencies | 4 |
| Unpacked size | 140.8 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| Provenance | attested (GitHub Actions) |
| GitHub stars | 2095 |
| Author | streamich |
| Maintainers | json-joy-team, streamich |
| Keywords | fsa, file system access, native file system, webfs, opfs, fs, filesystem, virtual, memory |

## Links

- npm: https://www.npmjs.com/package/@jsonjoy.com/fs-fsa
- Repository: https://github.com/streamich/memfs
- Homepage: https://github.com/streamich/memfs/tree/master/packages/fs-fsa
- Issues: https://github.com/streamich/memfs/issues
- Funding: https://github.com/sponsors/streamich
- npm.io page: https://npm.io/package/@jsonjoy.com/fs-fsa

## Dependencies (4)

- [thingies](https://npm.io/package/thingies.md) ^2.5.0
- [@jsonjoy.com/fs-core](https://npm.io/package/@jsonjoy.com/fs-core.md) 4.79.0
- [@jsonjoy.com/fs-node-utils](https://npm.io/package/@jsonjoy.com/fs-node-utils.md) 4.79.0
- [@jsonjoy.com/fs-node-builtins](https://npm.io/package/@jsonjoy.com/fs-node-builtins.md) 4.79.0

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## Recent versions

- 4.79.0 (latest) — 2026-09-22
- 4.78.1 — 2026-09-17
- 4.78.0 — 2026-09-13
- 4.77.0 — 2026-09-13
- 4.76.0 — 2026-09-12
- 4.75.0 — 2026-09-11
- 4.74.0 — 2026-09-10
- 4.73.0 — 2026-09-10
- 4.72.2 — 2026-09-10
- 4.72.1 — 2026-09-09
- 4.72.0 — 2026-09-09
- 4.71.1 — 2026-09-09
- 4.71.0 — 2026-09-04
- 4.70.0 — 2026-09-04
- 4.69.1 — 2026-09-02
- … 33 more at https://npm.io/package/@jsonjoy.com/fs-fsa/versions

## README

# @jsonjoy.com/fs-fsa

File System Access API implementation backed by `@jsonjoy.com/fs-core` primitives.

Provides a [File System Access API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API)
implementation that works with the `Superblock` filesystem abstraction.

## Installation

```bash
npm install @jsonjoy.com/fs-fsa
```

## Usage

```ts
import { fsa } from '@jsonjoy.com/fs-fsa';

const { dir, core, FileSystemObserver } = fsa({ mode: 'readwrite' });

// Create a file
const fileHandle = await dir.getFileHandle('hello.txt', { create: true });
const writable = await fileHandle.createWritable();
await writable.write('Hello, World!');
await writable.close();

// Read a file
const file = await fileHandle.getFile();
const contents = await file.text();
console.log(contents); // 'Hello, World!'
```

## License

Apache-2.0

---
_Source: https://npm.io/package/@jsonjoy.com/fs-fsa · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._