moai-workflow-ddd

Behavior-preserving refactoring uses AST analysis to understand code structure and characterization tests to lock in existing functionality, ensuring technical debt reduction introduces zero regressions during modernization.

Ast-grep enables semantic code manipulation for modernization by matching abstract syntax trees, allowing safe structural transformations while identifying and preserving domain boundaries within legacy monolithic services.

The best way to migrate APIs safely is using a structured cycle that leverages AST analysis for semantic manipulation and robust testing frameworks to validate functional equivalence before and after migration.

Yes, characterization tests are required to capture existing behavior before restructuring. They provide a robust safety net that validates functional equivalence when breaking down a monolithic service into modules.

AST analysis for refactoring should be avoided when there is no robust testing framework available to validate behavior preservation, as structural transformations without test validation risk introducing regressions.