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

75Health
Library PyPI

bcrypt (Python)

A Python library for secure password hashing using the bcrypt algorithm with an adjustable work factor

1,503
Apache 2.0
Used by 16
48Health
Library npm

swagger-ui-express

Serves interactive Swagger UI API documentation directly from your Express app based on a Swagger/OpenAPI JSON or YAML document.

1,495
MIT
Used by 16
60Health
Library Cargo

getrandom

A small, cross-platform Rust crate for retrieving random bytes directly from the OS

580
Other
Used by 16
87Health
Framework PyPI

Django

The high-level Python web framework that turns database models into secure, working web applications in record time.

91,063
BSD 3
Used by 15
92Health
Framework PyPI

django-rest-framework

The most widely-used toolkit for building Web APIs on top of Django, with serializers, viewsets, and a built-in browsable API.

30,179
BSD 3
Used by 15
46Health
Library PyPI

itsdangerous

A small Python toolkit for cryptographically signing data so you can trust it hasn't been tampered with when it comes back from an untrusted client.

3,134
BSD 3
Used by 15
40Health
Library PyPI

aiosqlite

Async/await-friendly wrapper around Python's built-in sqlite3 module for asyncio applications.

1,575
MIT
Used by 15
69Health
Library npm

OTPAuth

HOTP and TOTP one-time password library for Node.js, Deno, Bun, and browsers

1,476
MIT
Used by 15
76Health
Library Cargo

curve25519-dalek

Pure-Rust group arithmetic over Curve25519 and Ristretto255

1,193
BSD 3
Used by 15
41Health
Library npm

node-md5

A tiny, dependency-light JavaScript function for computing MD5 hashes of strings, buffers, and byte arrays.

913
BSD 3
Used by 15
82Health
Library Cargo

tower-http

A collection of Tower middleware and utilities for building HTTP clients and servers in Rust

912
MIT
Used by 15
74Health
Framework npm

@apollo/server

Spec-compliant, production-ready GraphQL server for Node.js

13,952
MIT
Used by 14
60Health
Library npm

@apidevtools/swagger-parser

Parses, validates, and dereferences Swagger 2.0 and OpenAPI 3.x specs in Node.js and browsers

1,207
MIT
Used by 14
81Health
Library Cargo

aes-gcm

Pure Rust AES-GCM authenticated encryption with optional hardware acceleration

959
Other
Used by 14
78Health
Library Cargo

keyring-rs

Cross-platform Rust library for storing passwords and secrets in the OS-native credential store

766
Apache 2.0
Used by 14
53Health
Library PyPI

httpcore

A minimal, low-level HTTP client for Python with sync, async, and HTTP/2 support

547
BSD 3
Used by 14
72Health
Library npm

@fastify/cors

Official Fastify plugin that adds configurable CORS headers and preflight handling to any Fastify API.

497
MIT
Used by 14
73Health
Framework npm

Koa

Koa is an expressive, minimal Node.js web framework built on async functions for cleaner middleware and better error handling.

35,685
MIT
Used by 13
91Health
Framework Go

Echo

A minimalist, high-performance Go web framework with a radix-tree router, built-in middleware chain, and first-class HTTP/2 support.

32,705
MIT
Used by 13
89Health
Library PyPI

Authlib

The ultimate Python library for building OAuth 1/2 and OpenID Connect clients and servers.

5,419
BSD 3
Used by 13
77Health
Library PyPI

drf-spectacular

Sane, flexible OpenAPI 3.0/3.1/3.2 schema generation for Django REST Framework

2,860
BSD 3
Used by 13
44Health
Library Cargo

num_cpus

A small Rust crate for counting the logical and physical CPU cores on the current machine.

627
Other
Used by 13
38Health
Library PyPI

sniffio

A tiny Python library that detects which async framework (trio, asyncio, or curio) your code is currently running under.

153
Other
Used by 13
56Health
Library npm

Comlink

A tiny RPC library that makes Web Workers enjoyable to use in JavaScript

12,791
Apache 2.0
Used by 12

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