Backed by nearly 80,000 GitHub stars and recognized as one of the most popular developer tools in the open-source ecosystem, Hoppscotch delivers a complete API development platform that runs instantly in any browser with zero installation. The platform supports six protocols out of the box including REST with full HTTP method coverage, GraphQL with schema introspection and multi-column documentation, WebSocket for full-duplex communication, Socket.IO, MQTT for IoT messaging, and Server-Sent Events for real-time streaming. Request collections organize your API calls into logical groups with support for sub-folders, environment variables with scope inheritance, pre-request scripts and post-request test scripts written in JavaScript, and automatic code snippet generation in over twenty languages and frameworks. Teams can collaborate in real-time with shared workspaces, role-based access controls, and cloud synchronization across devices. Migration from Postman, Insomnia, or OpenAPI specifications happens with a single click import. The self-hosted edition deploys via Docker Compose with PostgreSQL for data persistence, supporting SSO authentication through SAML and OAuth providers, SMTP configuration with OAuth2, and admin dashboard for user management. The platform also ships as a native desktop application for macOS, Windows, and Linux with offline support, plus a CLI tool for running collections in CI/CD pipelines. A built-in proxy mode bypasses CORS restrictions during development, and an interceptor enables request debugging and response modification. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

MeterSphere is the open-source continuous testing platform that brings test management, API testing, and AI-powered automation into a single self-hosted environment. The Spring Boot Java backend handles test execution with the JMeter engine while the Vue.js frontend delivers a responsive interface for managing test cases, plans, defects, and reports across projects. The built-in AI assistant leverages large language models to auto-generate functional test cases and API interface definitions, reducing manual test creation effort. Test management covers the complete lifecycle from writing and reviewing cases in list or mind-map views, through test plan creation with single plans and plan groups, to defect tracking with customizable templates and workflow rules. API testing combines Postman-like ease of use with JMeter-level flexibility, supporting interface debugging with server-side and local execution, API definition with visual request and response editors, interface mocking with configurable headers and body parameters, scenario automation with visual orchestration, and detailed test reports with automatic generation. The system-organization-project hierarchy supports up to 30 users in the community edition with role-based access control, file management, and configurable notification channels. MySQL stores application data, Kafka handles message queuing, MinIO provides S3-compatible object storage, and Redis manages caching. The plugin marketplace extends testing capabilities and enables DevOps pipeline integration. On RepoCloud, deploy MeterSphere on a dedicated VPS with Docker, root SSH access, and complete control over your testing infrastructure, all under the GPLv3 license.

With over 330 GitHub stars and described as "OpenRouter, but for agent tools instead of models," Treg is the unified tool registry that gives your AI agent one base URL, one token, and instant access to approximately 2,800 cataloged endpoints across 56 providers — SEO and backlink analysis via Semrush and Moz, social media intelligence from TikTok and Instagram, people and company enrichment through Crunchbase and Hunter, media buying, scraping, and SERP data — all priced per call from fractions of a cent with no provider signup required. The FastAPI backend with PostgreSQL stores credential bindings and injects them server-side into every proxied request, ensuring API keys and OAuth tokens never touch the agent or local machine while every call is audit-logged. Teams register their own paid API accounts, OAuth connections, vendor CLIs like Stripe, GitHub CLI, Vercel, and gcloud, plus custom SKILL.md definitions — all callable by every teammate's agent through a single treg token with automatic credential injection. The evidence-based tool selector shows success rate, response speed, and last-seen timestamp for each provider, so agents pick tools on measured performance rather than guesswork. Bring-your-own-key routes bypass metering entirely, and the one-dollar free credit on every new team lets agents start calling immediately. The Vue.js web dashboard provides team management, audit logs, catalog browsing, and guided onboarding. Self-host with pip install tools-registry[server] on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache-2.0 licensed.

Yet Another API Development Environment delivers a self-hosted alternative to Postman designed from the ground up for teams that need secure, collaborative API development without sending sensitive credentials through third-party cloud services. The multi-user system manages team members with role-based permissions and supports external authentication through OAuth2 and OIDC providers, while all data persists in an H2 file-based database that survives container and server restarts. REST and WebSocket request testing includes environment variable substitution, request chaining, and Markdown documentation for each endpoint. The JavaScript scripting engine runs request and response scripts for automated testing and data extraction, with cron job scheduling and API-triggered execution for continuous integration workflows. Collections import directly from OpenAPI specifications and Postman exports, while outbound export generates request code in multiple languages and frameworks. The browser extension proxy for Chrome and Firefox routes requests through the user's browser to bypass CORS restrictions when testing localhost and internal APIs, with an alternative server-side proxy for headless environments. Single-file data import and export simplifies backup and migration between instances. The React and Vite frontend ships with dark mode enabled by default. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.