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

92Health
Library npm

postcss

A CSS transformation engine that parses styles into an AST, letting JS plugins lint, prefix, and rewrite CSS — the foundation beneath Autoprefixer, Tailwind, and 200+ other tools.

28,977
MIT
Used by 277
72Health
Library Cargo

serde_json

The de facto standard JSON library for Rust, built on the Serde serialization framework

5,638
Apache 2.0
Used by 113
94Health
Library npm

Marked

A fast, low-level Markdown compiler that parses CommonMark and GFM into HTML in Node.js, browsers, or the CLI.

37,214
MIT
Used by 112
76Health
Library Cargo

serde

A generic framework for serializing and deserializing Rust data structures efficiently and safely.

10,838
Other
Used by 109
82Health
Library npm

js-yaml

A fast, complete YAML 1.2 and 1.1 parser and serializer for JavaScript.

6,634
MIT
Used by 101
88Health
Library npm

yaml

A definitive TypeScript parser and stringifier for YAML, supporting 1.1 and 1.2 with comment and CST access.

1,692
Other
Used by 99
82Health
Library Cargo

reqwest

An ergonomic, batteries-included HTTP client for Rust, with async and blocking APIs.

11,845
Other
Used by 72
68Health
Library Cargo

tempfile

A secure, cross-platform Rust library for temporary files and directories that clean up automatically on drop.

1,468
Other
Used by 69
66Health
Library Cargo

base64

Correct, fast, and configurable base64 encoding and decoding for Rust, with pluggable alphabets and padding.

738
Apache 2.0
Used by 66
63Health
Library Cargo

url

A WHATWG-standard-compliant URL parser and manipulation library for Rust.

1,575
Apache 2.0
Used by 62
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
67Health
Library Cargo

sha2

Pure Rust implementation of the SHA-2 hash function family (SHA-224/256/384/512) with hardware-accelerated backends.

2,267
Other
Used by 61
77Health
Library Cargo

regex

Rust's finite-automata regex engine with guaranteed linear-time matching and no catastrophic backtracking.

4,038
Apache 2.0
Used by 59
73Health
Library Cargo

Chrono

Timezone-aware date and time handling for Rust, with correct calendar operations and flexible strftime-style formatting.

3,913
Other
Used by 59
90Health
Library Cargo

Clap

The most widely used command-line argument parser for Rust, with both derive and builder APIs.

16,725
Other
Used by 56
81Health
Library Cargo

uuid

Generate and parse UUIDs in Rust across every standardized version, from v1 to v8.

1,247
Other
Used by 56
78Health
Library npm

markdown-it

A fast, pluggable CommonMark-compliant Markdown parser and renderer for JavaScript, safe by default.

21,945
MIT
Used by 52
58Health
Library Cargo

tracing

Structured, application-level diagnostics for async Rust programs, built around scoped spans and events.

6,892
MIT
Used by 51
90Health
Library npm

Cheerio

The fast, flexible library for parsing and manipulating HTML and XML with a familiar jQuery-style API.

30,505
MIT
Used by 45
48Health
Library npm

unified

Parse, inspect, transform, and serialize content through syntax-tree plugins.

5,036
MIT
Used by 44
84Health
Library npm

sanitize-html

Allowlist-based HTML sanitizer that strips XSS vectors from untrusted markup while preserving the tags and attributes you choose to keep.

4,630
MIT
Used by 42
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
84Health
Library npm

cron-parser

Parse, validate, and iterate cron expressions in Node.js with full timezone and DST support.

1,495
MIT
Used by 34
84Health
Library npm

cRonstrue

Turns cron expressions into human-readable descriptions, in 30+ languages.

1,636
MIT
Used by 33

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