OpenAPI Server

Summary

OpenAPI Server is ranked #16 of 25 in API mocking tools on Samsung Mobile US Press. It runs on API, Self-hosted.

Compared on API mocking tools

Dynamic responses

Yesgithub.com

OpenAPI import

Yesgithub.com

Request matching

pathgithub.com

Local deployment

Yesgithub.com

Supported protocols

http, httpsgithub.com

Facts

Purpose

OpenAPI Server is a local mock server for development that can proxy requests to a real backend.github.com · 4 Oct 2026

Intended use

The README describes using it to mock services while prototyping a single-page application without a working backend.github.com · 4 Oct 2026

End-to-end testing

Mocks can provide predictable API responses for end-to-end tests.github.com · 4 Oct 2026

OpenAPI support

It validates OpenAPI 3 and Swagger/OpenAPI 2 YAML specifications.github.com · 4 Oct 2026

Multiple specifications

It supports multiple specification files and directories and checks paths and methods for conflicts.github.com · 4 Oct 2026

Mock formats

Mocks can be JSON files, JavaScript modules, or Express middleware.github.com · 4 Oct 2026

Proxy and validation

It can proxy requests to another server and optionally validate responses.github.com · 4 Oct 2026

Other features

The README lists a static file server, HTTP and HTTPS support, watch mode, and configuration through environment variables, files, or CLI parameters.github.com · 4 Oct 2026

Integration

The project is an Express web server and can be used programmatically as an application or Express router, with custom Express middleware support.github.com · 4 Oct 2026

Install

The README instructs users to install it from its GitHub repository with npm.github.com · 4 Oct 2026

Default behavior

Mocks are enabled by default and take precedence over proxying when a matching mock exists.github.com · 4 Oct 2026

Notable limits

JavaScript mocks must run at runtime; the README says TypeScript mock files are not allowed because they cannot be transpiled at runtime.github.com · 4 Oct 2026

Publishing security

The README says npm releases use GitHub Actions OIDC trusted publishing with provenance.github.com · 4 Oct 2026

Maker location

The Intesys GitHub organization profile lists Italy as its location.github.com · 4 Oct 2026

Use case

The README describes using it to develop a single-page application before its backend is ready and to run end-to-end tests with predictable API responses.github.com · 5 Oct 2026

Mocking

Mocks can be JSON files, JavaScript modules, or Express middleware, and mocks are enabled by default.github.com · 5 Oct 2026

Proxy

When proxying is enabled, valid requests without a matching mock are forwarded to the configured backend.github.com · 5 Oct 2026

Response validation

The server can optionally validate responses.github.com · 5 Oct 2026

Additional features

It supports serving static files, HTTP and HTTPS, watch mode, and custom Express middleware.github.com · 5 Oct 2026

Configuration

Configuration is available through command-line options, environment variables, and environment files.github.com · 5 Oct 2026

Runtime requirement

The package declares Node.js version 18 or later as its engine requirement.github.com · 5 Oct 2026

License

The package declares the ISC license.github.com · 5 Oct 2026

Installation

The README gives a GitHub-based npm install command and a quick start that serves the API at localhost:3000/api.github.com · 5 Oct 2026

Where it ranks on Samsung Mobile US Press

• Best API Mocking Tools in 2026#16 of 25

Sources

• github.com/intesys/openapi-server· checked 4 Oct 2026
• github.com/intesys· checked 4 Oct 2026
• github.com/intesys/openapi-server/blob/master/pack· checked 5 Oct 2026