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Datafile versioning for Optimizely X Full Stack projects

This article is about datafile versioning. For details about how to access the datafile, try this article.
relevant products:
  • Optimizely X Full Stack

  • Understand datafile versioning
  • Debug and troubleshoot an Optimizely X Full Stack experiment 

To maintain backwards compatiblity with older SDK versions, Optimizely maintains multiple versions of the datafile. Datafile versioning ensures that apps that haven't been upgraded to the latest version of the SDK can still run experiments. For each SDK project, Optimizely uploads the datafile once per datafile version.

For example, for project ID "123," if we have 3 versions of the datafile, we will upload the following three files to the CDN:

The Optimizely X Full Stack dashboard always shows the path to the latest datafile version. In this case, that would be  The latest version would also be accessible at

If you’re using Full Stack SDKs to manage synchronizing the datafile from Optimizely, you don’t need to interface with different datafile versions directly. The SDK will make sure to use older versions of the datafile for older versions of the SDK.

See additional resources
Here are all our articles about the Optimizely dashboard, which you'll use to create projects, add collaborators, manage privacy settings, and more: 

Here's our developer documentation, where you'll find code samples, full references for our SDKs, and getting started guides.