Lightweight service virtualization/ API simulation / API mocking tool for developers and testers

Over the wire test doubles

Eliminate API integration headaches with Specmatic's no-code AI-powered API development suite. Teams ship APIs 10x faster by transforming specifications into executable contracts instantly—no coding required, no integration surprises.

Camouflage is a backend mocking tool for HTTP, gRPC, Websockets and Thrift protocols, which helps you carry out your front end prototyping, unit testing, functional/performance testing in silos, in absence of one or more Microservices/APIs.

HTTP mock for Golang: record and replay HTTP/HTTPS interactions for offline testing

Java binding for Hoverfly

Service Virtualization Solution – a combined Service Stub and Transparent Proxy

AI-Mocks is a Kotlin-based mock server toolkit that brings service virtualization to both HTTP/SSE and LLM APIs — think WireMock meets local OpenAI/Anthropic/Gemini/A2A testing, but with real streaming and Server-Sent Events support.

A .Net Library for Hoverfly

Stubbing tool for HTTP calls to allow more comprehensive + deterministic tests

A fluent Java API for virtualizing HTTP services. Service virtualization simplified. No endpoint configuration. Import/export of request-response pairs.

Bokor is a simple, Record and Playback Mock Server written in Node.js, utilized for Service Virtualization.

Service Virtualized HTTP - to help service test automation stay fast and consistent

Stub and validate HTTP endpoints with ease.

Admin dashboard for Hoverfly

A mountebank client written in Go.

Servirtium Overview

Hoverfly integration for pytest

Mokksy is a mock HTTP server built with Kotlin and Ktor

Service Virtualized HTTP - to help service test automation stay fast and consistent - for Go projects

Service Virtualized HTTP - to help service test automation stay fast and consistent - for Rust projects

A service virtualization proxy tool to monitor, record, playback, and mock web services and database calls

Service Virtualization example using WireMock standalone with JSON files to map the request and responses and Docker to create a persistent container to enable the long-living service.

Smocker is a network mocking tools for java application follow on twitter : https://twitter.com/SmockerJava

Service virtualisation example for the Simulations API

This is a teaching material aimed to demonstrate the peculiarities of testing distributed systems.

A Python version of Servirtium

Service Virtualized HTTP - to help service test automation stay fast and consistent - for JavaScript/Node projects

High-performance, multi-protocol mock server. HTTP, WebSocket, gRPC, MQTT, SSE, GraphQL, SOAP in one binary.

Install Hoverfly (https://docs.hoverfly.io) so that other GitHub Actions can use it easily (e.g. for testing)