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
Library npm

Axios

Promise-based HTTP client for the browser and Node.js with interceptors, automatic transforms, and cancellation

109,212
MIT
Used by 190
86Health
Framework npm

Express

The fast, unopinionated, minimalist web framework for Node.js

69,454
MIT
Used by 158
96Health
Library npm

OpenTelemetry JavaScript (@opentelemetry/api)

Vendor-neutral tracing, metrics, and context API that libraries and apps instrument once, so any OpenTelemetry-compatible backend can consume it.

3,467
Apache 2.0
Used by 91
95Health
SDK npm

Stripe Node.js Library

The official Node.js and TypeScript library for the Stripe API, giving developers a fully typed client for payments, billing, and Connect.

4,504
MIT
Used by 80
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
79Health
Library npm

MSW (Mock Service Worker)

Seamless REST and GraphQL API mocking for browser and Node.js

18,203
MIT
Used by 57
96Health
SDK npm

@slack/web-api

Slack's official Node.js HTTP client for calling any of the 270+ Web API methods, with built-in queuing, retries, pagination, and rate-limit handling.

3,378
MIT
Used by 38
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
97Health
SDK npm

google-api-nodejs-client

Google's officially supported Node.js client library for calling hundreds of Google APIs with built-in OAuth 2.0, API key, and service-account auth.

12,249
Apache 2.0
Used by 33
90Health
Library npm

Pinia

Intuitive, type-safe, and flexible state management store for Vue applications.

14,720
MIT
Used by 31
85Health
Library npm

express-rate-limit

Basic IP rate-limiting middleware for Express to throttle repeated requests and protect public APIs and sensitive endpoints.

3,305
MIT
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
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
81Health
Library Go

chi

A lightweight, idiomatic Go HTTP router built entirely on net/http, for composing middleware and mounting REST APIs without a framework.

22,827
MIT
Used by 22
90Health
Library npm

Scalar API Reference

Interactive, embeddable API reference documentation generated from your OpenAPI or Swagger specs.

16,101
MIT
Used by 22
73Health
SDK npm

octokit.js

The all-batteries-included GitHub SDK for browsers, Node.js, and Deno.

7,845
MIT
Used by 21
60Health
Library Cargo

jsonwebtoken

Create and decode JSON Web Tokens in Rust in a strongly typed way

2,089
MIT
Used by 16
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
80Health
SDK npm

@octokit/core

Extendable client for GitHub's REST and GraphQL APIs

1,285
MIT
Used by 15
91Health
Library Go

kin-openapi

A Go library for parsing, validating, converting, and working with OpenAPI 2.0, 3.0, 3.1, and 3.2 documents.

3,293
MIT
Used by 14
93Health
SDK npm

@notionhq/client

The official JavaScript and TypeScript client for the Notion API, with typed methods for every endpoint.

5,663
MIT
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
93Health
SDK PyPI

Stripe Python

Official Python bindings for the Stripe API, covering payments, billing, and Connect.

2,046
MIT
Used by 13
91Health
SDK npm

Svix

Official JavaScript/TypeScript client for the Svix webhook delivery API and signature verification.

3,404
MIT
Used by 12

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