Now Poseidon for UML is based on our Poseidon for DSLs platform. It is a great UML tool with a complete set of diagrams (class, package, use case, state, component, activity and sequence diagrams) and excellent user interface. We provide magnificent improvements in stability, scalability, performance, reliability and customization. We believe this tool has the best user interface in the industry. At the same time, it is an example of what is possible with our DSL platform. UML now is just one of the conceivable DSLs possible with the Poseidon for DSLs platform. A considerable part of the tool is generated from a handfull of models (MDSD). You, as the author of a DSL can simply change these models and by that create your own DSL modeling tool that shares the same user interface and performance characteristics as Poseidon for UML 8.0. Read on for our guiding principles.