Entity-sticky-routing ranking feature prefetch in microservice architecture

One or more storage media storing instructions which, when executed by the one or more processors, cause:

• in response to receiving a content request:
• determining an entity identifier of an entity associated with the content request;
• determining a host of a second service that is different than the first service;
• sending, by the first service, to the host of the second service, the entity identifier;
• in response to receiving the entity identifier from the first service, retrieving, by the second service executing on the host, entity feature data that is associated with the entity identifier;
• identifying, by the first service, a set of content delivery campaigns;
• in response to identifying the set of content delivery campaigns:
• identifying, by the first service, the host of the second service;
• sending, by the first service, to the host of the second service, an identity of the set of content delivery campaigns;
• based on the entity feature data, determining, by the host of the second service, a ranking of the set of content delivery campaigns;
• selecting a subset of the set of content delivery campaigns based on the ranking;
• causing data about each content delivery campaign in the subset to be transmitted over a computer network to a computing device.