Retrieving all experiment values for a specific user in a single server-side call can be achieved using the Statsig server SDKs.
The SDK allows for the evaluation of experiments on the fly for a given user without incurring a network roundtrip. This is particularly useful for server-side rendering scenarios, such as with Next.js, where you may have both server-side rendered (SSR) and client-side rendered (CSR) pages and wish to avoid wrapping your entire application with a CSR provider.
By using the server SDK, you can download the entire configuration and evaluate experiments for each user server-side. This approach scales well as it does not require a network call for each experiment evaluation, ensuring efficient performance even as user traffic increases.
For more information on how to implement this in your application, you can refer to the Node.js server SDK documentation provided by Statsig.