Hosted API simulations from your OpenAPI specs.

Push to GitHub, get a dedicated simulation URL in seconds. No config, no servers, no accounts to create.

You push code
  -> GitHub Action packages your OpenAPI specs
  -> Mockzilla provisions a dedicated simulation in your nearest AWS region
  -> Live at {label}.api.mockz.io

Main, each pull request and each branch you deploy get a host of their own:

• {label}.api.mockz.io for main, where the label is your repo name
• {label}-pr12.api.mockz.io for pull request 12
• {label}-{branch}.api.mockz.io for another branch your workflow deploys (feature/checkout becomes featurecheckout)

Every push updates the simulation. When the PR closes, the simulation is torn down automatically.

Add this to .github/workflows/mockzilla.yml:

name: Mockzilla

on:
  push:
    branches: [main]
  pull_request:
    types: [opened, synchronize, reopened, closed]

jobs:
  simulate:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      pull-requests: write
    steps:
      - uses: actions/checkout@v4
      - uses: mockzilla/actions@v1
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          services-dir: services  # one folder per API, each with its OpenAPI spec

Push. That's it. No API keys, no secrets, no signup.

Or start from a template: mockzilla-portable-template / mockzilla-codegen-template

brew tap mockzilla/tap
brew install mockzilla
mockzilla https://petstore3.swagger.io/api/v3/openapi.json

• Spec-driven simulation that matches your API contract exactly, with realistic response generation
• PR environments where every pull request gets its own URL
• Your choice of AWS region for each simulation
• Two modes: portable (just specs) or codegen (typed Go handlers with custom logic)
• Rate limit headers on every response for integration testing
• API key auth to protect simulations when needed

• mockzilla.org
• Install
• Contact