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hritik sharma
hritik sharma

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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 applications faster

All of this happens directly in the browser without modifying the application code.

Why This Is Useful

  • This approach helps developers:

  • continue development without waiting for backend APIs

  • simulate multiple scenarios quickly

  • test UI behavior under different conditions

  • speed up debugging and testing workflows

Full Technical Article

I wrote a detailed blog post explaining the architecture, implementation, and examples.

You can read the full article here:

👉 Medium Article:


https://medium.com/@hritik4november2003/tired-of-waiting-for-backend-apis-i-built-a-chrome-extension-to-simulate-them-31466f42ed52

Top comments (1)

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hritik_sharma_411 profile image
hritik sharma

Feedback is welcome! If you have suggestions for improving this idea or features that would make it more useful, I’d love to hear them.