Dev servers and API mocking

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• @kubb/plugin-redocGenerate a ReDoc API reference page with Kubb. Produces a standalone HTML file you can host without a build step.
• @stacksjs/ts-fakerts-mocker is a performance-focused and lightweight faker/data mocking library for TypeScript.
• @kubb/plugin-mcpGenerate Model Context Protocol (MCP) tool definitions with Kubb. Expose your REST APIs as AI-callable tools for LLMs, Claude, ChatGPT, and other AI assistants.
• wildcard-mock-linkapollo client mocking
• prisma-generator-fake-dataThe easiest way to generate mock data based on your Prisma models!
• @fakerjs/stringString package provides functionality to generate a fake string value.
• sinon-mongooseSinon extensions for Mongoose stubs
• interface-forgeA TypeScript library for creating strongly typed mock data factories using Faker.js for test data generation
• storybook-mirageA Storybook addon to use and interact with a MirageJS server
• @kubb/plugin-vue-queryGenerate type-safe TanStack Query (Vue Query) composables with Kubb. Covers useQuery, useMutation, useInfiniteQuery, and queryOptions with Vue 3 Composition API support.
• vite-plugin-mock-serverVite mock server plugin
• vitest-auto-spyAuto-generate fully-typed test spies from a class — across Vitest, Bun, node:test and Rstest, with Angular/NestJS/React/Vue/Svelte recipes. Drop-in replacement for jest-auto-spies and jasmine-auto-spies.
• babel-plugin-mockable-importsBabel plugin for mocking ES imports
• react-router-enzyme-contextA helper for mocking react router v4 context and childContextTypes when testing components with Enzyme mount() and shallow().
• bunyan-adaptorMaps the major Bunyan/Pino logging methods to custom methods
• @amadeus-it-group/kassetteDevelopment server, used mainly for testing, which proxies requests and is able to easily manage local mocks.
• counterfactTurn an OpenAPI document into a useful local API for frontend development in one command.
• openapi-mock-express-middlewareGenerates express mock-servers from OpenAPI specs
• jest-mock-nowDate.now() as deterministic Jest mock function.
• @zitterorg/magni-eos[![github actions][actions-image]][actions-url] [![coverage][codecov-image]][codecov-url] [![dependency status][deps-svg]][deps-url] [![dev dependency status][dev-deps-svg]][dev-deps-url] [![License][license-image]][license-url] [![Downloads][downloads-im
• create-test-serverCreates a minimal Express server for testing
• graphql-query-test-mockMock queries to your GraphQL backend in your Jest tests.
• rollup-plugin-deva development server for rollup
• google-drive-mockMock-Server that simulates being google-drive. Used for testing.
• bgprocSimple process manager for agents
• @webhooksite/cliA console utility used to interact with the Webhook.site API and proxy/forward/tunnel requests from a Webhook.site URL to any destination on your local network.
• zodockA library for generating mock data based on Zod schemas
• icedfrisby-nockConcise support for mock requests in IcedFrisby
• @test-effective/fakesTest Effective Fakes
• mocker-data-generatorA simplified way to generate mock data, builds using a simple schema and with the FakerJs
• socket-vcr-testRecord your test suite's HTTP interactions and replay them during future test runs for fast, deterministic, accurate tests.
• @alenon/grpc-mock-servergRPC mock server written on typescript
• chronokinesisModule for testing time-dependent code
• vitest-mmsmongodb-memory-server integration for vitest
• @graphql-mocks/network-nockMock using graphql-mocks with Nock
• @webjsdev/serverThe server for WebJs, a full-stack JavaScript framework built on web components with server-side rendering and no build step. Provides the file-based router, SSR, server actions, route handlers, middleware, and live reload on Node 24+ or Bun.
• mongodb-memory-server-global-4.4MongoDB Server for testing (auto-download 4.4 version to ~/.cache/mongodb-binaries).
• @stuntman/clientStuntman - HTTP proxy / mock API client
• @async-fn/jestAdditional methods to jest.fn to introduce "late resolve" of promises returned by mock functions. This allows tests that read chronologically, like a story.
• @simulacrum/auth0-simulatorRun local instance of Auth0 API for local development and integration testing
• vcr-testRecord your test suite's HTTP interactions and replay them during future test runs for fast, deterministic, accurate tests.
• wirepigBetter testing through the power of sockets.
• vite-console-forward-pluginA Vite plugin that forwards browser console logs to the Vite dev server console
• @cruglobal/graphql-ergonomockAutomatic mocking of GraphQL operations.
• dev-process-managerdev-process-manager is a Node.js process manager for local development environments that need multiple processes. It can be easily integrated into existing Node.js projects.
• json-server-authAuthentication middleware for JSON Server
• mock-cloud-firestoreMock library for Cloud Firestore
• @stuntman/serverStuntman - HTTP proxy / mock server with API
• @simulacrum/foundation-simulatorBase simulator to build simulators for integration testing.
• @aryzing/bun-mock-fetchMock fetch requests in Bun.

• msw vs json-server
• @copilotkit/aimock vs mock-socket
• mockttp vs ts-mockito
• mock-socket vs ts-mockito
• rewire vs ng-mocks
• msw vs miragejs
• mock-socket vs ng-mocks
• fast-check vs rewire