Abstract: Devices and techniques are generally described for ranking of search results based on multiple objectives. A first ranking for a plurality of search results is determined using a first machine learning model optimized for a first objective for ranking search results. A second objective for ranking search results is determined. A constraint is determined for the at least one second objective. The first machine learning model is iteratively updated to generate an updated machine learning model by minimizing a cost of the first objective subject to the constraint, wherein violations of the constraint are penalized using a penalty term. A second ranking for the plurality of search results is determined using the updated machine learning model. The search results of the second ranking are reordered relative to the search results of the first ranking.