instant-openapi-mock-server

I was tired of setting up Stripe sandbox accounts just to test if my frontend doesn't break on a 429. So I found this thing called Connexions and honestly it kind of changed how I work.

Drop your OpenAPI spec in a folder. Push to GitHub. Get a working API. That's literally it.

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What I use this for

• Testing my frontend against Stripe without a real Stripe account
• Simulating slow responses to see if my loading states actually work
• Running integration tests in CI without calling any real APIs
• Showing the backend team what I expect before they build anything

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How to get started

1. Hit Use this template up top
2. Drop your .yaml spec into openapi/
3. Push to main
4. Download the binary from Releases and run it

./your-repo-name

Your API is running. Go test something.

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The folder structure

openapi/
  stripe.yaml     →  available at /stripe/
  binance.yaml    →  available at /binance/
  whatever.yaml   →  available at /whatever/

Multiple APIs, one server, one port. I used to run three separate Prism instances for this. Never again.

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You also get a public URL

Push to main and Mockzilla gives you a hosted version automatically:

https://api.mockzilla.org/gh/{your-org}/{your-repo}/

Open PRs get their own preview URL too. Pretty useful for sharing with teammates.

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Powered by

• Connexions — the engine doing the heavy lifting
• Mockzilla — hosting and the GitHub Action

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Not affiliated with Stripe, Binance, or any other API you throw at this.