1. A model transformation unit adapted to transform a first source model in a source domain into a target model in a target domain, the first source model comprising a tree of source elements and the target model comprising a tree of target elements representing a project to be implemented in computer code, the model transformation unit comprising: at least one memory adapted to store the first source model, a source meta-model representing the source domain, a target meta-model representing the target domain, and a transformation model indicating rules for transforming between said source meta-model and said target meta-model; and a transformation engine adapted to determine, based on said transformation model, a parent element of each target element of the target model to be generated and to construct said target model by generating, for each source element in said source model to be transformed, a target element based on said transformation model, and by positioning each target element in the tree of target elements below its parent element.