Supporting multiple feature binding strategies in NX

Feature-oriented programming (FOP) toolkits restrict implementers of software product lines to certain implementation choices. One is left with the choices between, for example, class-level or object-level extensions and between static or dynamic feature bindings. These choices are typically made at an early development stage causing an unwanted lock-in. We present a feature-oriented development framework based on dynamic, object-oriented constructs for deferring such design decisions by piggybacking on first-class language entities (metaclasses, mixins). A framework proto-type is available for the scripting language NX. NX provides the required object-oriented language infrastructure: a reflective language model, metaclasses, multiple class-based inheritance, decorator mixins, and open entity declarations. We exemplify the approach based on a Graph Product Line.