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As preliminary information, Jira issues are assigned to a given version by specifying the "Fix Version" field. 

Besides thisMoreover, Jira ensures that changes are tracked under the History section, which is available in the corresponding issue screen, so you know who changed what and when.

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Xray addresses versioning the Jira way, which we think is more elegant, while at . At the same time, it ensures data consistency:

• Whenever you schedule a Test for execution in a Test Execution, Xray creates an instance of the Test that we call a Test Run. That Test Run contains the "version"/revision of the Test specification at that moment.
• You can go to an already recorded Test Run and reset the specification to the last/actual specification on the Test issue. Or, you can merge it, which means that only changed steps will be updated and the other step results are not changed. More info can be found in the Execute Tests page.  
• Normally, you work with the last "version"/revison of the Test (as you do for a user story, etc.). However, if you really want to manage different versions of Tests at same time (assuming that they're actually different), you can create different Tests, one per version.

By persisting the Test specification on the Test Runs,  Xray ensures data consistency. The "version" of the Test that was executed in a Test Run , is persisted in the Test Run itself. That means that if you change a Test specification today, that won't affect your already recorded runs for that Test (unless you want to).

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