Open Source API Development & Testing Tools

fastapi ★ 102K

FastAPI framework, high performance, easy to learn, fast to code, ready for production

Hoppscotch ★ 80K

Sleek, intuitive API development and testing platform

Bruno ★ 47K

Lightweight, fast, and open-source API client for developers

Insomnia ★ 40K

Powerful API development and testing made effortless

one-api ★ 37K

LLM API 管理 & 分发系统，支持 OpenAI、Azure、Anthropic Claude、Google Gemini、DeepSeek、字节豆包、ChatGLM、文心一言、讯飞星火、通义千问、360 智脑、腾讯混元等主流模型，统一 API 适配，可用于 key 管理与二次分发。单可执行文件，提供 Docke

OpenAPI-Specification ★ 31K

The OpenAPI Specification Repository

openapi-generator ★ 27K

OpenAPI Generator allows generation of API client libraries (SDK generation), server stubs, documentation and configuration automatically given an OpenAPI Spec

redoc ★ 26K

📘 OpenAPI/Swagger-generated API Reference Documentation

SafeLine ★ 23K

SafeLine is a self-hosted WAF(Web Application Firewall) / reverse proxy to protect your web apps from attacks and exploits.

Mobile-Security-Framework-MobSF ★ 22K

Mobile Security Framework (MobSF) is an automated, all-in-one mobile application (Android/iOS/Windows) pen-testing, malware analysis and security assessment fra

grpc-gateway ★ 20K

gRPC to JSON proxy generator following the gRPC HTTP spec

Yaak ★ 19K

Fast, secure, offline API client with Git integration

hurl ★ 19K

Hurl, run and test HTTP requests with plain text.

Apache APISIX ★ 17K

High-performance API gateway with built-in LLM support

Scalar ★ 16K

Open-source API documentation and testing platform

swag ★ 13K

Automatically generate RESTful API documentation with Swagger 2.0 for Go.

fastapi_mcp ★ 12K

Expose your FastAPI endpoints as Model Context Protocol (MCP) tools, with Auth!

Tyk ★ 11K

Universal API management for REST, GraphQL, gRPC & async

higress ★ 9.4K

🤖 AI Gateway | AI Native API Gateway

django-ninja ★ 9.2K

💨 Fast, Async-ready, Openapi, type hints based framework for building APIs

api-platform ★ 9.2K

🕸️ Create REST and GraphQL APIs, scaffold Jamstack webapps, stream changes in real-time.

karate ★ 9.0K

Test Automation Made Simple

shenyu ★ 8.8K

Apache ShenYu is a Java native API Gateway for service proxy, protocol conversion and API governance.

Ocelot ★ 8.7K

.NET API Gateway

litestar ★ 8.5K

Light, flexible and extensible ASGI framework | Built to scale

Mockoon ★ 8.4K

Effortless API mocking for seamless development

openapi-typescript ★ 8.4K

Generate TypeScript types from OpenAPI 3 specs

xh ★ 8.1K

Friendly and fast tool for sending HTTP requests

Tailcall ★ 7.6K

The modern GraphQL runtime

swagger-core ★ 7.5K

Examples and server integrations for generating the Swagger API Specification, which enables easy access to your REST API

wiremock ★ 7.4K

A tool for mocking HTTP services

NSwag ★ 7.4K

The Swagger/OpenAPI toolchain for .NET, ASP.NET Core and TypeScript.

gpt-load ★ 6.8K

Self-hosted AI gateway for multi-channel, multi-credential setups — API keys and subscription accounts, scheduling, failover, request logs and usage. 自托管 AI 网关：

aws-sam-cli ★ 6.7K

CLI tool to build, test, debug, and deploy Serverless applications using AWS SAM

RWKV-Runner ★ 6.5K

A RWKV management and startup tool, full automation, only 8MB. And provides an interface compatible with the OpenAI API. RWKV is a large language model that is

goa ★ 6.1K

Design-first Go framework that generates API code, documentation, and clients. Define once in an elegant DSL, deploy as HTTP and gRPC services with zero drift b

cypress-realworld-app ★ 5.9K

A payment application to demonstrate real-world usage of Cypress testing methods, patterns, and workflows.

typia ★ 5.9K

Super-fast/easy runtime validators and serializers via transformation

easegress ★ 5.9K

A Cloud Native traffic orchestration system. (CNCF Project)

open-connector ★ 5.8K

Open-source auth gateway connecting 1500+ SaaS providers to AI agents through SDK, CLI, MCP, HTTP, and OpenAPI.

kgateway ★ 5.7K

The Cloud-Native API Gateway and AI Gateway

notion-sdk-js ★ 5.7K

Official Notion JavaScript Client

orpc ★ 5.6K

Typesafe APIs Made Simple 🪄

hey-api ★ 5.4K

👨‍🚀 Turn API specifications into production-ready SDKs, validators, mocks, and more. 20+ plugins. Millions of weekly npm downloads. Used by Vercel, OpenCode,

serverless-express ★ 5.3K

Run Express and other Node.js frameworks on AWS Serverless technologies such as Lambda, API Gateway, Lambda@Edge, and more.

go-restful ★ 5.1K

package for building REST-style Web Services using Go

mockserver-monorepo ★ 5.0K

MockServer is an HTTP(S) mock server and proxy for testing that lets you mock APIs, inspect and modify live traffic, and inject failures. It supports HTTP/1.1,

spring-cloud-gateway ★ 4.9K

An API Gateway built on Spring Framework and Spring Boot providing routing and more.

agentgateway ★ 4.9K

Next Generation Agentic Proxy for AI Agents and MCP servers

autorest ★ 4.8K

OpenAPI (f.k.a Swagger) Specification code generator. Supports C#, PowerShell, Go, Java, Node.js, TypeScript, Python

Integuru ★ 4.8K

The first AI agent that builds permissionless integrations through reverse engineering platforms' internal APIs.

emissary ★ 4.5K

open source Kubernetes-native API gateway for microservices built on the Envoy Proxy

mcp-context-forge ★ 4.5K

An AI Gateway, registry, and proxy that sits in front of any MCP, A2A, or REST/gRPC APIs, exposing a unified endpoint with centralized discovery, guardrails and

optillm ★ 4.3K

Optimizing inference proxy for LLMs

octelium ★ 4.1K

A next-gen FOSS self-hosted unified zero trust secure access platform that can operate as a remote access VPN, a ZTNA platform, API/AI/MCP gateway, a PaaS, an n

HTTPie ★ 4.0K

Modern command-line HTTP client for the API era

claudia ★ 3.9K

Deploy Node.js projects to AWS Lambda and API Gateway easily

nba_api ★ 3.8K

An API Client package to access the APIs for NBA.com

ATAC ★ 3.7K

A simple API client (postman like) in your terminal

curlie ★ 3.7K

The power of curl, the ease of use of httpie.

Zappa ★ 3.7K

Serverless Python

kubernetes-client ★ 3.7K

Java client for Kubernetes & OpenShift

schemathesis ★ 3.6K

Catch API bugs before your users do

php-curl-class ★ 3.3K

PHP Curl Class makes it easy to send HTTP requests and integrate with web APIs

run-aspnetcore-microservices ★ 3.3K

Microservices on .NET platforms used ASP.NET Web API, Docker, RabbitMQ, MassTransit, Grpc, Yarp API Gateway, PostgreSQL, Redis, SQLite, SqlServer, Marten, Entit

ruby-openai ★ 3.2K

OpenAI API + Ruby! 🤖❤️ GPT-5 & Realtime WebRTC compatible!

cc-gateway ★ 3.0K

AI API identity gateway — reverse proxy that normalizes device fingerprints and telemetry for privacy-preserving API proxying

gateway ★ 3.0K

Manages Envoy Proxy as a Standalone or Kubernetes-based Application Gateway

WindsurfAPI ★ 3.0K

Turn Windsurf / Devin Desktop's 100+ AI models (Claude, GPT, Gemini, DeepSeek, Kimi, GLM, SWE) into OpenAI-, Anthropic- & Gemini-compatible APIs. Zero-dependenc

apidash ★ 2.9K

API Dash is a beautiful AI-powered open-source cross-platform (Desktop & Mobile) API Client built using Flutter which can help you easily create & customize you

Restfox ★ 2.8K

Offline-First Minimalistic HTTP & Socket Testing Client for the Web & Desktop

Krakend ★ 2.7K

Blazing-fast API gateway with linear scalability

Firecamp ★ 2.6K

Unified API development ecosystem for modern teams

kiro-gateway ★ 2.3K

👻 Proxy API gateway for Kiro IDE & CLI (Amazon Q Developer / AWS CodeWhisperer). Use free Claude models with any client.

api-umbrella ★ 2.2K

Open source API management platform

notion-sdk-py ★ 2.2K

Notion API client SDK, rewritten in Python! (sync + async)

microcks ★ 2.0K

The open source, cloud native tool for API Mocking and Testing. Microcks is a Cloud Native Computing Foundation incubating project 🚀

resterm ★ 1.9K

Terminal API client for HTTP, GraphQL and gRPC. Plain .http files you can diff and version, with workflows, mocks, profiling, tracing, OpenAPI import, SSH tunne

AngusTester ★ 1.8K

AI-native software testing platform — one YAML test language covering API, Web, mobile, messaging, data, and LLM scenarios. Self-hostable.

pythagora ★ 1.8K

Generate automated tests for your Node.js app via LLMs without developers having to write a single line of code.

Voiden ★ 1.8K

Build APIs like code with Git-native workspace

WireMock.Net ★ 1.7K

WireMock.Net is a flexible product for stubbing and mocking web HTTP responses using advanced request matching and response templating. Based on WireMock Java,

DPP ★ 1.4K

C++ Discord API Bot Library - D++ is Lightweight and scalable for small and huge bots!

algoliasearch-client-javascript ★ 1.4K

⚡️ A fully-featured and blazing-fast JavaScript API client to interact with Algolia.

smocker ★ 1.3K

Smocker is a simple and efficient HTTP mock server and proxy

WunderGraph ★ 1.3K

Unify APIs, databases, and services effortlessly

php-vcr ★ 1.2K

Record your test suite's HTTP interactions and replay them during future test runs for fast, deterministic, accurate tests.

macai ★ 931

All-in-one native macOS AI chat application for virtually any AI provider

aimock ★ 930

Mock everything your AI app talks to — LLM APIs, MCP, A2A, AG-UI, vector DBs, search. One package, one port, zero dependencies.

binance ★ 926

Node.js & JavaScript SDK for Binance REST APIs & WebSockets, with TypeScript & browser support, integration tests, beautification & more.

mockttp ★ 883

Powerful friendly HTTP mock server & proxy library

apitest ★ 846

A simple and extensible behavioural testing library for Go. You can use api test to simplify REST API, HTTP handler and e2e tests.

dev-proxy ★ 831

Simulate API failures, throttling, and chaos — all from your command line.

just-api ★ 814

:boom: Test REST, GraphQL APIs

greenmail ★ 744

Official master for the Greenmail project

portman ★ 685

Port OpenAPI Specs to Postman Collections, inject test suite and run via Newman 👨🏽‍🚀

httpmock ★ 667

HTTP mocking library for Rust

runn ★ 649

runn is a package/tool for running operations following a scenario.

pactum ★ 620

REST API Testing Tool for all levels in a Test Pyramid

serenity-js ★ 616

A TypeScript-native acceptance testing framework that gives your Playwright Test, WebdriverIO, or Cucumber test suite the architecture it needs to scale.

mocker-api ★ 500

mocker-api that creates mocks for REST APIs. It will be helpful when you try to test your application without the actual REST API server.

Hive ★ 483

Open-source GraphQL federation platform

Gravitee ★ 456

Unified API, event, and AI agent management platform