
Open-Source API Development Ecosystem • https://hoppscotch.io • Offline, On-Prem & Cloud • Web, Desktop & CLI • Open-Source Alternative to Postman, Insomnia

Hoppscotch is an open-source API development ecosystem that provides a lightweight, fast alternative to Postman and Insomnia. It enables developers to design, test, and collaborate on APIs across web, desktop, and CLI platforms with support for offline and on-premise deployments.
Hoppscotch is ideal for backend developers, API engineers, QA testers, and development teams who need a flexible, open-source alternative to commercial API clients. It serves both individual developers and organizations requiring on-premise or offline-capable API development solutions.

Playwright is a framework for Web Testing and Automation. It allows testing Chromium, Firefox and WebKit with a single API.

Opensource IDE For Exploring and Testing API's (lightweight alternative to Postman/Insomnia)

The open-source, cross-platform API client for GraphQL, REST, WebSockets, SSE and gRPC. With Cloud, Local and Git storage.

OpenAPI Generator allows generation of API client libraries (SDK generation), server stubs, documentation and configuration automatically given an OpenAPI Spec (v2, v3)

Scalar is an open-source API platform: 🌐 Modern REST API Client 📖 Beautiful API References ✨ 1st-Class OpenAPI/Swagger Support

Free and open-source API Client & Interceptor.

A list of Free Software network services and web applications which can be hosted on your own servers

Get up and running with Kimi-K2.5, GLM-5, MiniMax, DeepSeek, gpt-oss, Qwen, Gemma and other models.

Production-ready platform for agentic workflow development.

Production-ready platform for agentic workflow development.

User-friendly AI Interface (Supports Ollama, OpenAI API, ...)

Virtual whiteboard for sketching hand-drawn like diagrams

JavaScript API for Chrome and Firefox

JavaScript API for Chrome and Firefox

The world’s fastest framework for building websites.

Playwright is a framework for Web Testing and Automation. It allows testing Chromium, Firefox and WebKit with a single API.