1. A schema generator, comprising: a computer readable storage medium; computer software stored on the computer readable storage medium and operable to parse a plurality of transaction definitions for a software system, wherein each transaction definition comprises one or more parameters; generate a plurality of schema definitions in response to the plurality of transaction definitions, wherein the schema definitions are written in a self-describing language; wherein a first schema definition is operable to map the one or more parameters associated with a first transaction definition to a first document written in the self-describing language; and wherein a second schema definition is operable to map a second document written in the self-describing language to the one or more parameters associated with a second transaction definition.