# @libp2p/peer-collections

> Stores values against a peer id

Latest version **7.0.30** (published 2026-10-17) · Apache-2.0 OR MIT license · 0 weekly downloads

## Install

```sh
npm install @libp2p/peer-collections
pnpm add @libp2p/peer-collections
yarn add @libp2p/peer-collections
bun add @libp2p/peer-collections
```

## Health

**Score 75/100 (B)** — status: active.

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

Warnings: low downloads.

## Facts

| | |
|---|---|
| Version | 7.0.30 |
| Published | 2026-10-17 |
| First published | 2022-03-02 |
| Weekly downloads | 0 |
| License | Apache-2.0 OR MIT |
| TypeScript types | bundled |
| Module format | ESM |
| Dependencies | 4 |
| Unpacked size | 910.1 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| Provenance | attested (GitHub Actions) |
| GitHub stars | 2584 |
| Maintainers | daviddias, alanshaw, achingbrain, vascosantos, npm-service-account-libp2p, jacobheun |
| Keywords | IPFS |

## Links

- npm: https://www.npmjs.com/package/@libp2p/peer-collections
- Repository: https://github.com/libp2p/js-libp2p
- Homepage: https://github.com/libp2p/js-libp2p/tree/main/packages/peer-collections#readme
- Issues: https://github.com/libp2p/js-libp2p/issues
- npm.io page: https://npm.io/package/@libp2p/peer-collections

## Dependencies (4)

- [multiformats](https://npm.io/package/multiformats.md) ^14.0.0
- [@libp2p/utils](https://npm.io/package/@libp2p/utils.md) ^7.4.3
- [@libp2p/peer-id](https://npm.io/package/@libp2p/peer-id.md) ^6.0.17
- [@libp2p/interface](https://npm.io/package/@libp2p/interface.md) ^3.4.0

## Recent versions

- 7.0.30 (latest) — 2026-10-17
- 7.0.30-f0e64b9b8 (next) — 2026-10-17
- 7.0.30-57c4b4456 — 2026-10-17
- 7.0.30-6d888970e — 2026-10-17
- 7.0.29-be63a4416 — 2026-10-16
- 7.0.29-e48eabf67 — 2026-10-16
- 7.0.29-e073d373d — 2026-10-15
- 7.0.29-4a416447c — 2026-10-12
- 7.0.29-974e63f20 — 2026-10-11
- 7.0.29-5c4cdb2d6 — 2026-10-10
- 7.0.29 — 2026-10-10
- 7.0.28-e724dd173 — 2026-10-10
- 7.0.28-9441e049a — 2026-10-10
- 7.0.28-fc90066f8 — 2026-10-08
- 7.0.28-40480a034 — 2026-10-05
- … 918 more at https://npm.io/package/@libp2p/peer-collections/versions

## README

# @libp2p/peer-collections

[![libp2p.io](https://img.shields.io/badge/project-libp2p-yellow.svg?style=flat-square)](http://libp2p.io/)
[![Discuss](https://img.shields.io/discourse/https/discuss.libp2p.io/posts.svg?style=flat-square)](https://discuss.libp2p.io)
[![codecov](https://img.shields.io/codecov/c/github/libp2p/js-libp2p.svg?style=flat-square)](https://codecov.io/gh/libp2p/js-libp2p)
[![CI](https://img.shields.io/github/actions/workflow/status/libp2p/js-libp2p/main.yml?branch=main\&style=flat-square)](https://github.com/libp2p/js-libp2p/actions/workflows/main.yml?query=branch%3Amain)

> Stores values against a peer id

# About

<!--

!IMPORTANT!

Everything in this README between "# About" and "# Install" is automatically
generated and will be overwritten the next time the doc generator is run.

To make changes to this section, please update the @packageDocumentation section
of src/index.js or src/index.ts

To experiment with formatting, please run "npm run docs" from the root of this
repo and examine the changes made.

-->

We can't use PeerIds as collection keys because collection keys are compared using same-value-zero equality, so this is just a group of collections that stringifies PeerIds before storing them.

PeerIds cache stringified versions of themselves so this should be a cheap operation.

Tracked versions are also available which report their current size to the libp2p Metrics collector.

## Example - Peer lists

```TypeScript
import { peerList } from '@libp2p/peer-collections'
import { peerIdFromPrivateKey } from '@libp2p/peer-id'
import { generateKeyPair } from '@libp2p/crypto/keys'

const peerId = peerIdFromPrivateKey(await generateKeyPair('Ed25519'))

const list = peerList()
list.push(peerId)
```

## Example - Tracked peer lists

```TypeScript
import { trackedPeerList } from '@libp2p/peer-collections'
import { peerIdFromPrivateKey } from '@libp2p/peer-id'
import { generateKeyPair } from '@libp2p/crypto/keys'
import { createLibp2p } from 'libp2p'

const libp2p = await createLibp2p()
const peerId = peerIdFromPrivateKey(await generateKeyPair('Ed25519'))

const list = trackedPeerList({ name: 'my_metric_name', metrics: libp2p.metrics })
list.push(peerId)
```

## Example - Peer maps

```TypeScript
import { peerMap } from '@libp2p/peer-collections'
import { peerIdFromPrivateKey } from '@libp2p/peer-id'
import { generateKeyPair } from '@libp2p/crypto/keys'

const peerId = peerIdFromPrivateKey(await generateKeyPair('Ed25519'))

const map = peerMap<string>()
map.set(peerId, 'value')
```

## Example - Tracked peer maps

```TypeScript
import { trackedPeerMap } from '@libp2p/peer-collections'
import { createLibp2p } from 'libp2p'
import { peerIdFromPrivateKey } from '@libp2p/peer-id'
import { generateKeyPair } from '@libp2p/crypto/keys'

const libp2p = await createLibp2p()
const peerId = peerIdFromPrivateKey(await generateKeyPair('Ed25519'))

const map = trackedPeerMap({ name: 'my_metric_name', metrics: libp2p.metrics })
map.set(peerId, 'value')
```

## Example - Peer sets

```TypeScript
import { peerSet } from '@libp2p/peer-collections'
import { peerIdFromPrivateKey } from '@libp2p/peer-id'
import { generateKeyPair } from '@libp2p/crypto/keys'

const peerId = peerIdFromPrivateKey(await generateKeyPair('Ed25519'))

const set = peerSet()
set.add(peerId)
```

## Example - Tracked peer sets

```TypeScript
import { trackedPeerSet } from '@libp2p/peer-collections'
import { createLibp2p } from 'libp2p'
import { peerIdFromPrivateKey } from '@libp2p/peer-id'
import { generateKeyPair } from '@libp2p/crypto/keys'

const libp2p = await createLibp2p()
const peerId = peerIdFromPrivateKey(await generateKeyPair('Ed25519'))

const set = trackedPeerSet({ name: 'my_metric_name', metrics: libp2p.metrics })
set.add(peerId)
```

## Example - Peer filters

```TypeScript
import { peerFilter } from '@libp2p/peer-collections'
import { peerIdFromPrivateKey } from '@libp2p/peer-id'
import { generateKeyPair } from '@libp2p/crypto/keys'

const peerId = peerIdFromPrivateKey(await generateKeyPair('Ed25519'))

const filter = peerFilter(1024)
filter.has(peerId) // false
filter.add(peerId)
filter.has(peerId) // true
```

# Install

```console
$ npm i @libp2p/peer-collections
```

## Browser `<script>` tag

Loading this module through a script tag will make its exports available as `Libp2pPeerCollections` in the global namespace.

```html
<script src="https://unpkg.com/@libp2p/peer-collections/dist/index.min.js"></script>
```

# API Docs

- <https://libp2p.github.io/js-libp2p/modules/_libp2p_peer-collections.html>

# License

Licensed under either of

- Apache 2.0, ([LICENSE-APACHE](https://github.com/libp2p/js-libp2p/blob/main/packages/peer-collections/LICENSE-APACHE) / <http://www.apache.org/licenses/LICENSE-2.0>)
- MIT ([LICENSE-MIT](https://github.com/libp2p/js-libp2p/blob/main/packages/peer-collections/LICENSE-MIT) / <http://opensource.org/licenses/MIT>)

# Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

---
_Source: https://npm.io/package/@libp2p/peer-collections · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._