A system and method for interfacing additional translation logic via composer(s) to a compiler to extend the capabilities of the compiler is provided. Generally, composer(s) can be software libraries that provide employment of componentization and polymorphism to compiler add-ons in order to extend compiler capabilities. One or more composers can be accessible to the compilation process by reference(s) made in a source code file. For example, additional translation logic for data types and/or expressions (e.g., markup language) created after compiler design can be made accessible to a compiler via composer(s), thus extending the existing compiler. The present invention mitigates problems associated with conventional compiler extending schemes and affords for compile code optimization without having to consider substantially all of the operations of a single query.