2. A method according to claim 1 , wherein: said building said graph includes populating said data structure; said identifications of vertices include one or more unique identifications and information about software for one or more vertices; said identifications of edges include one or more unique identifications and indications of two or more vertices; said identifications of inputs identifies at least one vertex; and said identifications of outputs identifies at least one vertex.
2. A method according to claim 1 , wherein: said building said graph includes populating said data structure; said identifications of vertices include one or more unique identifications and information about software for one or more vertices; said identifications of edges include one or more unique identifications and indications of two or more vertices; said identifications of inputs identifies at least one vertex; and said identifications of outputs identifies at least one vertex. 4. A method according to claim 2 , wherein said building said graph comprises: combining a first data structure with a second data structure to create a particular data structure; and adding additional edges from outputs of a sub-graph associated with first data structure to inputs of a sub-graph associated with second data structure.