1. A system, comprising: a processor; and a memory storing a program, which, when executed on the processor, performs an operation for ranking search results received from a plurality of distinct search resources, the operation comprising: receiving a search query over a communications network from a software application executing on a client device; transmitting the search query to a plurality of search resources via the communications network; receiving, from each of the plurality of search resources, a set of ranked search results, wherein each search result identifies an item and wherein each search result includes metadata characterizing the item and a link to a full version of the item; determining a unified match score for each search result in the received sets of ranked search results by summing matching scores of each search result ranked below the respective search result in the respective received set of ranked search results, wherein a unified match score of a first ranked search result is determined based on metadata of the first ranked search result and metadata of each second ranked search result having a lower rank than the first ranked search result in the associated set of ranked search results and wherein the metadata characterizing items identified in each ranked search result includes a title of the item and a summary of the item; determining a unified ranking for the ranked search results in the received sets of ranked search results based on the determined unified match scores for each search result, wherein the unified ranking maintains a relative ranking of each set of ranked search results as received from the plurality of search resources; ordering the search results by the determined unified ranking; generating a presentation of the ordered search results, wherein each respective search result included in the presentation comprises the link to the full version of the respective item identified by the respective search result; and sending the presentation of the ordered search results over the communications network to the software application executing on the client device.