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

95Health
Tool npm

ESLint

The pluggable JavaScript and TypeScript linter that finds and fixes code problems through a fully customizable, plugin-based rule engine.

27,504
MIT
Used by 368
91Health
Tool npm

prettier

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

52,263
MIT
Used by 310
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.

28,972
MIT
Used by 277
94Health
Tool npm

typescript-eslint

The official meta-package bundling the TypeScript ESLint parser, plugin, and rule presets behind a single typed config() helper.

16,391
MIT
Used by 260
64Health
Library npm

react-markdown

Safely render Markdown as React elements, no dangerouslySetInnerHTML required

15,878
MIT
Used by 164
95Health
Library npm

@babel/core

The core JavaScript compiler that transforms next-generation syntax into code every browser and runtime can understand.

43,996
MIT
Used by 163
75Health
Library Cargo

serde_json

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

5,636
Apache 2.0
Used by 111
56Health
Library npm

fs-extra

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

9,589
MIT
Used by 84
90Health
Framework PyPI

FastAPI

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

102,333
MIT
Used by 76
60Health
Library npm

diff

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

9,207
BSD 3
Used by 70
92Health
Library npm

undici

A fast, spec-compliant HTTP/1.1 client for Node.js, built from scratch with zero runtime dependencies

7,695
MIT
Used by 70
83Health
Library npm

Pino

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

18,194
MIT
Used by 67
50Health
Library npm

React Syntax Highlighter

A React component for syntax-highlighting code blocks using highlight.js or Prism ASTs, with JavaScript-based styles and no external stylesheet required.

4,674
MIT
Used by 59
60Health
Library npm

Winston

A battle-tested Node.js logging library with pluggable transports, custom formats, and multiple log levels.

24,520
MIT
Used by 50
66Health
Library npm

remark

A plugin-powered markdown processor that parses, transforms, and serializes markdown on top of unified.

8,995
MIT
Used by 48
93Health
Library PyPI

urllib3

A powerful, user-friendly HTTP client for Python with thread-safe connection pooling, TLS verification, and retry handling.

4,058
MIT
Used by 48
68Health
Library npm

proxy-agent

Maps HTTP, HTTPS, SOCKS, and PAC proxy protocols to the correct Node.js http.Agent implementation automatically.

1,161
MIT
Used by 47
62Health
Library PyPI

rich

A Python library for rendering rich text, tables, progress bars, and syntax-highlighted code in the terminal.

57,363
MIT
Used by 46
90Health
Tool PyPI

Ruff

An extremely fast Python linter and code formatter, written in Rust, built as a drop-in replacement for Flake8, Black, isort, and dozens of plugins.

49,630
MIT
Used by 46
90Health
Library npm

Prisma Client

Auto-generated, type-safe database client for Node.js and TypeScript.

47,610
Apache 2.0
Used by 46
86Health
Library PyPI

typing_extensions

Backported and experimental type-hint features for Python, usable on older interpreters and ahead of the stdlib.

582
Other
Used by 45
85Health
Library PyPI

PyJWT

A Python implementation of RFC 7519 for encoding, decoding, and verifying JSON Web Tokens.

5,700
MIT
Used by 44
48Health
Library npm

unified

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

5,030
MIT
Used by 44
92Health
SDK npm

@clickhouse/client

The official TypeScript client for connecting Node.js applications to ClickHouse over HTTP.

331
Apache 2.0
Used by 38

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