Domain-Specific Languages (DSL’s) offer language-level abstractions that General-purpose languages do not offer, thereby speeding up the implementation of the solution of problems within a specific domain. Developers have the choice of developing a DSL by building an interpreter/compiler for it, which is a hard and time-consuming task, or embedding it in a host language, thus speeding up the development process but losing several advantages that having a dedicated compiler might bring. In this work we present a meta-compiler called Metacasanova, whose meta-language is based on operational semantics. We then propose a language extension with functors and modules that allows to embed the type system of a language definition inside the meta-type system of Metacasanova and improves the performance of manipulating data structures at run-time. Our result shows that Metacasanova drastically reduces the code lines required to develop a compiler, and that the running time of the Meta-program is improved by embedding the host Language type system in the meta-type system with the use of functors in the meta-language.