In some aspects, a model of a remote data source is defined. The model includes an entity representing a data segment from the remote data source. The entity has properties, which represent fields of a data structure in the remote data source and have data type descriptors indicating data types used by the fields. The model also includes an attribute specifying a function, which uses the properties as inputs. The entity is matched to exported data from the remote data source, and the exported data is used as input data to the attribute's function.