Directory

Open Source Packages

Libraries, frameworks, tools, and SDKs used by the apps in this directory — scored the same way as the apps themselves.

5929 packages

All Packages

67Health
Library npm

JSZip

Create, read, and edit ZIP files directly in JavaScript, in the browser or Node.js.

10,386
Other
Used by 66
79Health
Library npm

PapaParse

The fastest in-browser CSV parser for JavaScript, with streaming, Web Workers, and zero dependencies

13,576
MIT
Used by 61
74Health
Library npm

qs

A battle-tested querystring parser and serializer for Node.js with nested object support and built-in security limits.

8,943
BSD 3
Used by 49
44Health
Library npm

buffer

The Node.js Buffer API, reimplemented for the browser on top of Uint8Array.

1,891
MIT
Used by 42
50Health
Library npm

mime-types

The ultimate JavaScript content-type utility for resolving MIME types from file extensions and paths.

1,476
MIT
Used by 41
82Health
Library npm

body-parser

Node.js body-parsing middleware that turns raw HTTP request bodies into ready-to-use req.body objects.

5,499
MIT
Used by 36
51Health
Library npm

superjson

Serialize JavaScript to a superset of JSON that keeps Dates, Maps, Sets, BigInts, and more intact.

5,281
MIT
Used by 32
38Health
Library npm

gray-matter

Fast, dependable front-matter parser for YAML, JSON, TOML, and CoffeeScript metadata blocks

4,491
MIT
Used by 31
54Health
Library npm

cookie

Basic HTTP cookie parser and serializer for HTTP servers, with zero dependencies and full RFC 6265 support.

1,535
MIT
Used by 31
47Health
Library npm

node-xml2js

XML-to-JavaScript-object parser and builder for Node.js

4,959
MIT
Used by 19
93Health
Library npm

protobuf.js

A fast, conformant JavaScript and TypeScript implementation of Protocol Buffers, no protoc required

10,595
Other
Used by 17
77Health
Library npm

smol-toml

A small, fast, spec-compliant TOML parser and serializer for JavaScript

311
BSD 3
Used by 17
47Health
Library npm

SheetJS (xlsx-republish)

A drop-in npm mirror of the SheetJS Community Edition for reading and writing spreadsheets.

36,347
Apache 2.0
Used by 16
91Health
Library npm

Protobuf-ES

A conformance-tested, ESM-first Protocol Buffers runtime and code generator for modern JavaScript and TypeScript.

1,666
Apache 2.0
Used by 16
89Health
Library npm

@xmldom/xmldom

A pure JavaScript, W3C-standard DOMParser and XMLSerializer for parsing and building XML/HTML documents

469
MIT
Used by 14
67Health
Library npm

json-2-csv

Converts arrays of JSON documents to RFC 4180 compliant CSV and back, with native support for nested sub-documents.

458
MIT
Used by 8
78Health
Library npm

Apache Arrow JS

The official JavaScript/TypeScript implementation of Apache Arrow's columnar in-memory format for fast, zero-copy data interchange.

112
Apache 2.0
Used by 8
61Health
Library npm

feed

Generate RSS 2.0, Atom 1.0, and JSON Feed 1.0 syndication feeds from a single TypeScript API.

1,411
MIT
Used by 7
55Health
Library npm

toml-node

A zero-dependency, spec-compliant TOML parser for Node.js with BigInt and Temporal support.

326
MIT
Used by 6
47Health
Library npm

xml-js

Converts XML text to JavaScript objects or JSON and back, preserving element order.

1,339
MIT
Used by 5
71Health
Library PyPI

FlatBuffers

Google's memory-efficient, zero-copy serialization library for cross-language data exchange

26,520
Apache 2.0
Used by 3
36Health
Library npm

yaml.js

Standalone JavaScript YAML 1.2 parser and encoder for Node.js and browsers, with yaml2json and json2yaml command-line tools.

884
MIT
Used by 3
35Health
Library Cargo

serde-wasm-bindgen

Native integration of Serde with wasm-bindgen for fast Rust-to-JavaScript value conversion

613
MIT
Used by 3
48Health
Library Cargo

sourcemap

A Rust library for parsing, generating, and rewriting JavaScript sourcemaps, built and maintained by Sentry.

248
BSD 3
Used by 2

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