Refactoring versus restructuring

Developers sometimes co-opt terms that sound cool and make them into broader synonyms, as is the case for refactoring. As defined by Martin Fowler, refactoring is the process of restructuring existing computer code without changing its external behavior. For many developers, refactoring has become synonymous with change, but there are key differences.

It is exceedingly rare that a team refactors an architecture: rather, they restructure it, making substantive changes to both structure and behavior. Architecture patterns exist in part to make certain architectural characteristics primary in an application. Switching patterns entails switching priorities, which isn't refactoring. For example, architects might choose an EDA for scalability. If the team siwtches to a different architectural pattern, it likely won't support the same level of scalability.

Neal Ford, Rebecca Parsons & Patrick Kua, "Building Evolvable Architectures", in Building Evolutionary Architectures: Support Constant Change, 99.