1. A machine-accessible medium of a storage device containing instructions of a computer readable program effective, when executing in a data processing system, to cause said data processing system to perform operations comprising: generating session preferences by a module of the computer readable program, the session preferences including a selection of one or more assertion schemas for use in generating one or more assertions, the selected assertion schemas each having one or more associated design attributes; parsing the design to determine locations in the design for the one or more assertions based on architecture, structure, and hierarchy of the design; and generating the one or more assertions based on the session preferences, the determined locations for the one or more assertions, and the design attributes associated with the selected assertion schema, wherein generating the one or more assertions comprises: instantiating the selected assertion schema; generating assertion snippets based on the instantiated assertion schema and session preferences and associated design attributes; and embedding the assertion snippets in the design, source code, or in a design assertion file.