Domain-Specific Languages (DSLs) allow building software applications by simplifying the labour of both software engineers and domain experts thanks to the abstraction provided by a high-level code. Introducing a DSL in the software development process requires the use of technologies and frameworks in the design and implementation activities. If we are restricted to web-client applications, then XML-based languages and JavaScript frameworks and widgets are commonly used and combined in order to provide fast, robust and flexible solutions. Under this scenario, we have developed the PsiEngine, an interpreter able to evaluate programs coded in high-level XML-based DSLs (XML-DSLs) to provide solutions to domain specific problems within a web-c...