Introducing Versioning for Mock APIs in WireMock Cloud

API simulations tend to change over time. This can be due to changes made to the simulated API endpoint, or to better represent responses and application scenarios.   The ability to quickly update mock APIs makes them much more useful, but also adds fragility: a single tweak can break testing workflows and leave the team wondering who changed what and why.

That’s why we’re adding versioning to WireMock Cloud, now available in private beta. Every change to a mock API is automatically captured as a commit: stubs, settings, schemas, imports, chaos rule – everything. You can explore the full history, inspect diffs, and restore previous versions, either at the level of a single stub or the entire mock.

Watch Dan demo versioning:

Why this is useful:

• Review history: Every commit is captured and timestamped. If your QA engineer reports that yesterday’s regression tests suddenly failed, you can open the history, see that a teammate modified a response stub at 3 p.m., and immediately understand what changed.
  
  
• Inspect diffs: Diffs are shown side by side. Imagine you’ve been testing against an authentication flow that suddenly returns 401 instead of 200. By looking at the diff of the stub, you can confirm that someone added an extra header requirement, giving you clarity on why your tests broke.
  
  
• Roll back: You can roll back a single stub or the entire mock. Say you just imported an updated OpenAPI spec and realized it overwrote several carefully tuned stubs you still need. Instead of manually fixing them, you can restore the previous version in seconds, with the revert tracked as a new commit.
  
  

How to use versioning

From any mock API, click the Version history tab in the top menu bar

This opens a chronological list of all commits made to that mock. Each commit records when the change was made, which user made it, and what was affected.’

Browse and inspect changes
Click on a commit to drill into the details. You’ll see a breakdown of all stubs, settings, or imports that were added, modified, or removed. For editable content such as JSON stubs, you’ll get a side-by-side diff showing exactly what changed.

Compare with latest
If you want to understand how an earlier version stacks up against your current mock, use the Compare with latest option. This highlights every difference between then and now—useful for debugging regressions or reviewing a colleague’s edits.

Restore versions

• To revert a single stub or setting, open the commit, locate the change, and click Restore. That specific item will be rolled back, and a new commit will be created automatically.
  
  
• To roll back the entire mock, choose Compare with latest on the desired commit and hit Restore all changes. The full state of the mock will be reset to that version, again tracked as a new commit.

Move fast and don’t worry about breaking things 

Built-in versioning is another (small) step on our path to making WireMock Cloud the standard for enterprise-grade API simulation - in this case, by protecting your mock endpoints from breaking changes. We’re making it easier to build, test, and collaborate on mock APIs, so that your simulated environments can keep up with the velocity of your codebase updates. 

If you’ve got any feedback or questions, we’d love to hear from you.