Server Side Testing

Server-side testing: A type of A/B testing in which variations are generated and controlled on the server side, before the content is displayed to the user. Unlike client-side testing, where changes are applied in the browser via JavaScript, server-side testing enables us to test in-depth changes to business logic or the backend: recommendation algorithms, dynamic pricing, page structure, API integrations, etc.

In a CRO (Conversion Rate Optimization) approach, this method is particularly useful for :

• improve performance (reduce loading times, eliminate flickering),
• guarantee a consistent user experience from the very first rendering,
• test logic that is invisible to the user but has a high business impact.

However, it requires more technical resources (developers, version management, QA), and is often reserved for high-stakes tests.

Popular server-side testing tools:

• Optimizely
• AB Tasty (Feature experimentation)
• Dynamic Yield

‍