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

91Health
Tool npm

prettier

An opinionated code formatter that enforces consistent style across every language your project speaks.

52,316
MIT
Used by 310
78Health
Library npm

date-fns

Modern JavaScript date utility library with 200+ pure, immutable functions

36,647
MIT
Used by 202
94Health
Library npm

Axios

Promise-based HTTP client for the browser and Node.js with interceptors, automatic transforms, and cancellation

109,216
MIT
Used by 190
78Health
Library npm

Zustand

A small, fast React state management library with a hook-based API and no boilerplate.

58,763
MIT
Used by 119
78Health
Tool npm

eslint-plugin-import

ESLint rules that validate ES module import/export syntax and catch broken paths before they hit your build.

5,947
MIT
Used by 116
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
95Health
SDK npm

Sentry JavaScript (@sentry/browser)

The official Sentry SDK for capturing errors, performance traces, and session replays in browser JavaScript apps.

8,745
MIT
Used by 110
76Health
Library Cargo

serde

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

10,838
Other
Used by 109
93Health
Library PyPI

Pydantic

Data validation and settings management using Python type hints, backed by a Rust core.

28,891
MIT
Used by 104
96Health
Framework PyPI

pytest

The Python testing framework that makes writing small tests easy and scales to complex functional test suites.

14,543
MIT
Used by 100
95Health
Framework Cargo

Tokio

The async runtime powering most of Rust's networked, concurrent, and I/O-bound applications.

33,257
MIT
Used by 96
85Health
Library npm

@hookform/resolvers

Official React Hook Form adapters that plug 20+ schema-validation libraries — Zod, Yup, Joi, Valibot, ArkType and more — straight into useForm's resolver.

2,263
MIT
Used by 93
64Health
Library npm

fs-extra

Drop-in replacement for Node's fs module adding copy, remove, mkdirs, and JSON helpers with native promise support.

9,590
MIT
Used by 84
91Health
Framework PyPI

FastAPI

A modern, high-performance Python web framework for building APIs with automatic validation, serialization, and interactive docs.

102,676
MIT
Used by 78
58Health
Library npm

node-fetch

A lightweight, spec-compliant implementation of the browser Fetch API for Node.js

8,855
MIT
Used by 74
86Health
Library npm

highlight.js

Zero-dependency JavaScript syntax highlighter with automatic language detection for over 190 languages.

24,999
BSD 3
Used by 73
82Health
Library Cargo

reqwest

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

11,845
Other
Used by 72
63Health
Library npm

diff

A battle-tested JavaScript library for computing and applying text diffs at the character, word, line, sentence, CSS, or JSON level.

9,210
BSD 3
Used by 70
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
85Health
Library npm

Floating UI

React hooks and components for building accessible, perfectly positioned tooltips, popovers, and dropdowns.

32,753
MIT
Used by 68
85Health
Library npm

Pino

A super fast, low-overhead JSON logger for Node.js applications.

18,227
MIT
Used by 67
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
56Health
Tool npm

eslint-plugin-jsx-a11y

Static ESLint rules that catch JSX accessibility issues before code ships.

3,621
MIT
Used by 65

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