Mockoon

Mockoon is an open-source desktop app that allows users to design and run mock REST APIs. It functions as a tool for developers to simulate API responses without needing to write code or deploy to a remote server. The software is primarily used to reduce dependencies on external services, avoid rate limits, and test edge cases in a controlled environment where responses, status codes, and latencies are predictable.

The software is available as a desktop application for MacOS, Windows, and Linux, making it accessible across different operating systems. For headless environments and continuous integration pipelines, it provides a command line interface. Users can also deploy mocks to serverless environments such as AWS Lambda, GCP Functions, and Firebase Functions via a dedicated NPM package, allowing for flexible deployment strategies based on the project needs.

Key features

• Unlimited local servers and routes
• CLI for headless environments and CI
• Control over HTTP methods, status codes, and regex paths
• OpenAPI compatibility
• Request recording and logs
• JSON templating
• Proxy forwarding mode
• HTTPS support

Mockoon is built for developers who need to prototype APIs or onboard new team members with a reliable testing environment. It supports the import of OpenAPI specifications to speed up the setup process and allows for the serving of files and custom headers. By removing the need for a remote account or deployment for basic use, it enables a fast workflow for local development. While the core desktop application operates locally, an optional cloud service provides data synchronization and real-time collaboration features for teams.

It serves as a utility for API infrastructure and prototyping, focusing on local development and serverless deployment to streamline the integration of third-party services.