1. A computer-implemented method for dynamically generating classes and methods in memory in order for a host programming language to transmit or receive instance data to or from an application programming interface comprising: receiving a schema, which describes the format and properties of instance data to be transmitted or received; dynamically generating parser classes for deserialization based on the schema, wherein generating the parser classes comprises: iterating over each property defined in the schema and in any other schema referenced in the schema, generating a new parser class for each non-scalar, non-array property defined by the schema; for each property, reading associative values representing attributes of the property; generating a class variable based on the read associated values; and associating each generated class variable with one or more accessor and mutator methods to update and retrieve the class variables; and storing the generated parser classes and methods in memory in order for the host programming language to transmit or receive instance data to or from the application programming interface.