JUMBO is an OpenSource toolkit addressing the semantic and ontological impedances that are major barriers to interoperability in computational chemistry and physics. Users build XMLSchemas from generic XML components to support particular computational tasks, such as high-throughput chemistry. JUMBO components provide a complete semantic description of information to or from a code such as MOPAC or GAMESS. Codes are edited to use JUMBO libraries as adapters to program-independent XML objects, or output is transduced using a generic parser, JUMBOMarker. The JUMBO system is designed for flexible collaborative contributions.