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

65Health
Library PyPI

python-multipart

A fast, streaming multipart/form-data parser for Python that powers file uploads in FastAPI and Starlette.

531
Apache 2.0
Used by 43
44Health
Library npm

buffer

The Node.js Buffer API, reimplemented for the browser on top of Uint8Array.

1,891
MIT
Used by 42
51Health
Library npm

mime-types

The ultimate JavaScript content-type utility for resolving MIME types from file extensions and paths.

1,475
MIT
Used by 41
95Health
Framework PyPI

aiohttp

Asynchronous HTTP client and server framework for Python's asyncio, covering both API calls and building web/WebSocket services.

16,548
Apache 2.0
Used by 40
44Health
Library npm

crypto-js

A JavaScript library of crypto standards - hashing, HMAC, PBKDF2, and symmetric ciphers for Node.js and the browser.

16,409
MIT
Used by 40
82Health
Library npm

@hono/node-server

The official Node.js adapter that runs your Hono application on a native Node HTTP server using web-standard APIs.

676
MIT
Used by 37
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
90Health
Framework npm

tRPC Server

Build end-to-end typesafe APIs in TypeScript with no schemas, no code generation, and zero runtime bloat.

40,607
MIT
Used by 35
49Health
Library Go

mux

A lightweight, http.Handler-compatible Go router that matches requests by path, host, method, headers, and query, and can reverse them back into URLs.

21,836
BSD 3
Used by 35
44Health
Library npm

fflate

High-performance DEFLATE, GZIP, Zlib, and ZIP compression for JavaScript in an 8kB package.

3,009
MIT
Used by 35
75Health
Library Cargo

flate2

Streaming DEFLATE, gzip, and zlib compression for Rust with pluggable backends

1,124
Other
Used by 35
48Health
Library npm

bcrypt

Battle-tested password hashing for Node.js using the adaptive bcrypt algorithm.

7,803
MIT
Used by 34
89Health
Library npm

@hono/zod-validator

Type-safe request validation middleware for Hono, powered by Zod schemas.

992
MIT
Used by 34
90Health
Tool PyPI

Gunicorn

A fast, lightweight pre-fork WSGI and ASGI HTTP server for running Python web apps in production on UNIX.

10,669
MIT
Used by 33
72Health
Library npm

compression

Node.js middleware that transparently gzip-, deflate-, or Brotli-compresses HTTP responses for Express and raw http servers.

2,806
MIT
Used by 33
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
65Health
Library PyPI

Certifi

Mozilla's curated root CA bundle for verifying SSL/TLS certificates in Python.

997
MPL-2.0
Used by 32
38Health
Library npm

gray-matter

Fast, dependable front-matter parser for YAML, JSON, TOML, and CoffeeScript metadata blocks

4,490
MIT
Used by 31
64Health
Library npm

cookie

Basic HTTP cookie parser and serializer for HTTP servers, with zero dependencies and full RFC 6265 support.

1,534
MIT
Used by 31
76Health
Library Cargo

toml

A native Rust encoder and decoder for TOML with first-class Serde support.

1,073
Apache 2.0
Used by 31
98Health
Library PyPI

Protocol Buffers

Google's language-neutral, platform-neutral binary format for serializing structured data

72,037
BSD 3
Used by 30
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
70Health
Library npm

csv-parse

A flexible, dependency-free CSV parser for Node.js and the browser with stream, callback, and sync APIs.

4,287
MIT
Used by 29

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