1. A method comprising: receiving a specification for processing beacons, the beacons being associated with an event occurring at a client while a user is interacting with a web application and including unstructured data; parsing, by a computer system, the specification to determine an object model including objects determined from the specification, wherein different specifications are parsed into a format of the object model; determining, by the computer system, a generator from a set of generators, wherein each generator is configured to process the format of the object model to generate a different type of target program to process the beacons and multiple generators can process different specifications that are parsed into the format of the object model; and running, by the computer system, the generator with the object model to generate a target program configured to identify the beacons for the specification, determine unstructured data in the beacons that were specified in the specification, and transform the unstructured data into structured data as specified in the specification.