Initially present only in functional languages such as OCaml and Haskell, Algebraic Data Types have now become pervasive in mainstream languages, providing nice data abstractions and an elegant way to express functions through pattern matching. Numerous approaches have been designed to compile rich pattern matching to cleverly designed, efficient decision trees. However, these approaches are specific to a choice of memory representation which must accommodate garbage collection and polymorphism. ADTs now appear in languages more liberal in their memory representation. Notably, Rust is now introducing more and more memory optimisations. As memory representation and compilation are interdependent, it raises the question of pattern matching compilation for highly customised layouts. We propose to ease the experimentation of new, custom layouts in the early stages of compiler development by providing specification tools and a complete synthesis chain to generate pattern matching compilation procedures. In this report, we present a novel way to specify compositional memory layouts, for which we automatically synthesise elementary builders and accessors, yielding a correct representation-specific compilation algorithm. This approach is implemented in a prototype tool ribbit.