Server-side configuration variables in feature testing

A method includes receiving an identification of a feature associated with digital content of a third-party content provider, wherein the identification comprises a feature variable placeholder associated with the feature. The method further includes receiving a configuration of a feature flag associated with the feature. The method further includes determining, by a processing device of an experimentation system, a plurality of feature variable values corresponding to the feature variable placeholder. The method further includes configuring, by the processing device, one or more rules on the experimentation system to determine: when and to whom the feature is to be deployed, based on the feature flag; and which of the plurality of feature variable values is to be deployed when and to whom.