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
86Health
Tool npm

tsx

A drop-in replacement for the node CLI that runs TypeScript and ESM files instantly, powered by esbuild.

12,141
MIT
Used by 177
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
83Health
Library npm

Pino

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

18,194
MIT
Used by 67
72Health
Tool npm

css-loader

Resolves CSS @import and url() like JavaScript imports so webpack can bundle stylesheets and their assets.

4,320
MIT
Used by 65
61Health
Tool npm

style-loader

A webpack loader that injects bundled CSS into the DOM using style or link tags at runtime.

1,666
MIT
Used by 54
73Health
Tool npm

babel-loader

Babel loader for webpack (and Rspack) that transpiles modern JavaScript with filesystem caching and source map support.

4,835
MIT
Used by 51
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
82Health
Tool npm

sass-loader

Compiles Sass and SCSS files to CSS inside a webpack build, wiring in Dart Sass or Sass Embedded automatically.

3,891
MIT
Used by 48
90Health
Library npm

Prisma Client

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

47,610
Apache 2.0
Used by 46
85Health
Library PyPI

PyJWT

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

5,700
MIT
Used by 44
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
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
91Health
Library PyPI

jsonschema

The reference implementation of JSON Schema validation for Python, supporting every draft from 3 to 2020-12.

4,980
MIT
Used by 26
91Health
Framework npm

Fastify

A fast and low-overhead web framework for Node.js, built around schema-based validation and a plugin architecture

37,137
MIT
Used by 25
60Health
Library Go

gjson

Fast, dependency-light JSON value extraction for Go using dot-notation paths.

15,558
MIT
Used by 22
53Health
Library npm

jsonrepair

Repair invalid or broken JSON documents — missing quotes, trailing commas, truncation, and more

2,404
Other
Used by 21

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