Abstract: Methods, systems, and apparatus include computer program encoded on a computer-readable storage medium for conducting an experiment for a campaign. A subset of current campaign parameters from a third party can be received, by a computing system, to be a set of test variables, where the set of test variables correspond to a proposed modification of a current campaign that is applied to a treatment campaign. The current campaign can be monitored for changes to the current campaign parameters. Based on a determination that the current campaign parameter that has been modified by the third party is outside the set of test variables, the modification to the current campaign parameter can be reproduced and propagated to the treatment campaign. An action to take can be determined based on the modified current campaign parameter causing a change to at least one of the set of test variables.