Repository Index

Light, fluffy, and always free - The AWS Local Emulator alternative

• aws
• aws-emulation
• localstack
• devops

Open-source platform for creating safe, isolated production sandboxes for API, integration, and E2E testing.

• testing
• test-automation
• api-testing
• testing-tools

Web and API based SMTP testing

An email and SMTP testing tool with API for developers

• email-testing
• go
• golang
• smtp-server

Mockery is a simple yet flexible PHP mock object framework for use in unit testing with PHPUnit, PHPSpec or any other testing framework. Its core goal is to offer a test double framework with a succinct API capable of clearly defining all possible object operations and interactions using a human readable Domain Specific Language (DSL).

• mockery
• phpunit
• php
• stub

Catches mail and serves it through a dream.

• smtp
• mail
• server
• ruby

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, HTTP/2, gRPC, WebSockets, TCP and more on a single port, with additional support for HTTP/3, message brokers, and AI/LLM APIs.

• mock-server
• proxy
• java-client
• javascript-client

A gem providing "time travel", "time freezing", and "time acceleration" capabilities, making it simple to test time-dependent code. It provides a unified method to mock Time.now, Date.today, and DateTime.now in a single call.

• rails
• ruby
• time
• test

Papercut SMTP -- The Simple Desktop Email Server

• papercut
• smtp-server
• smtp
• testing

A tool for generating self-contained, type-safe test doubles in go

Free, open-source AWS emulator. LocalStack alternative: 107 services, 7,657 operations, true 100% Smithy conformance (258,545/258,545 variants pass). No account, no auth token, no paid tier.

• aws
• aws-emulator
• aws-testing
• dynamodb

Aioresponses is a helper for mock/fake web requests in python aiohttp package.

• aiohttp
• test
• mocking
• asyncio

Generate mocks from ActiveRecord models for unit tests that run fast because they don’t need to load Rails or a database.

Shift-left API Integration | Auto-fix integration drift before integration. Specmatic turns API specifications into executable contracts, continuously verifying that every change made by AI coding agents and engineers stays true to the desired behaviour. Ship AI-ready APIs 10x faster, from intent to implementation, with Spec-Driven API Development.

• contract-testing
• microservices
• contract-driven-development
• cdd

a socket mock framework - for all kinds of socket animals, web-clients included

• python
• testing
• mock
• socket

Simplify software testing, by easily mocking any system using HTTP/HTTPS, allowing a team to test and develop against a service that is not complete or is unstable or just to reproduce planned/edge cases.

• mock
• stub
• proxy
• proxy-server

SMTP mock server written on Golang. Mimic any 📤 SMTP server behavior for your test environment with fake SMTP server.

• smtp
• smtp-mock
• smtp-server
• smtp-mail

Mock an SSH server and define all commands it supports (Python, Twisted)

• mock
• ssh
• python
• hylang

💎 Ruby SMTP mock. Mimic any 📤 SMTP server behavior for your test environment with fake SMTP server.

• testing
• testing-tools
• ruby
• ruby-gem

http proxy with Elixir. wait request with multi port and forward to each URIs

• elixir
• http-proxy

a version of pythons unittest.Mock with async methods

Mocking functions. Please get in touch to discuss features! Only regular functions available for now.

localaik is a local compatibility server for a subset of the Gemini and OpenAI APIs. Run one container locally, point your SDK to it, and the proxy serves both protocol shapes on the same port for tests and development.

• docker
• gemini
• golang
• llama-cpp

Open-source simulation harness for testing AI agents. Simulate LLM and tool calls to test edge cases, failure paths, and agent logic without live API calls.

• ai-agents
• ai-testing
• llm
• llm-evaluation