I Built a Chrome Extension to Simulate API Responses Instantly

During software development, frontend work often depends on backend APIs that may not always be ready. This creates common challenges: waiting for backend APIs to be implemented testing error responses or edge cases simulating slow network responses verifying UI behavior with different payloads While there are tools available for API mocking, many of them require additional setup such as proxies or backend configuration. I wanted a simpler solution that works directly inside the browser. So I built a browser extension for Google Chrome that allows developers to intercept API requests and return custom responses instantly. What the Extension Does The extension lets developers define rules that match specific API requests. When a request matches a rule, the extension can return a mocked response instead of the original response from the server. This makes it possible to: test frontend features without backend dependencies simulate error responses test different payload structures debug a