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.

52,263
MIT
Used by 310
68Health
Library npm

date-fns

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

36,648
MIT
Used by 202
76Health
Library npm

Lodash

A modern JavaScript utility library delivering modularity, performance, and extras for arrays, objects, and functions.

61,278
MIT
Used by 194
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
82Health
Tool npm

eslint-plugin-import

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

5,944
MIT
Used by 116
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
91Health
Tool npm

rollup

A module bundler for JavaScript that compiles small pieces of code into optimized libraries and applications using native ES modules.

26,307
MIT
Used by 53
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
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
85Health
Library PyPI

PyJWT

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

5,700
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
84Health
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
65Health
Library npm

postcss-import

A PostCSS plugin that inlines @import rules, merging split CSS files into one stylesheet before other plugins run.

1,410
MIT
Used by 33
83Health
Library npm

type-fest

A collection of essential, ready-made TypeScript utility types beyond the built-in standard library.

17,409
Other
Used by 32
55Health
Library npm

superjson

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

5,277
MIT
Used by 32
87Health
Library npm

fast-xml-parser

Pure-JS XML parser, builder, and validator with no C/C++ bindings and no callbacks

3,139
MIT
Used by 32
45Health
Library npm

zod-to-json-schema

Converts Zod validation schemas into standard JSON Schema, ready for OpenAPI, OpenAI, and JSON Schema draft 7 consumers.

1,252
Other
Used by 30
45Health
Library npm

JSON5

JSON for humans: an extended JSON syntax with comments, trailing commas, and unquoted keys for hand-written config.

7,162
MIT
Used by 28

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