modernize

Run a gap analysis documenting the equivalence map and orphan patterns, write characterization tests capturing current behavior, then migrate one module per epic using the Strangler Fig pattern. Each epic must pass all characterization tests before being marked complete.

Document breaking changes and deprecated APIs in a gap analysis, commit a passing characterization test baseline, then migrate modules incrementally from infrastructure inward. Run the full characterization suite after every epic to catch regressions.

Characterization tests document what the system currently does, not what it should do. They cover public API contracts, business logic outputs, and integration boundaries, creating a regression baseline that must stay green throughout the migration.

No. The workflow enforces one module per epic because larger scopes overflow implementer context, prevent meaningful code review, and make rollback impossible. A cleanup epic always runs last to remove coexistence adapters.

The epic is not marked complete and the workflow stops. A debug skill is invoked to root-cause the failure before any fix, since a failing characterization test signals a behavioral regression introduced by the migration.

Big bang rewrites leave the project broken at every commit with no safe stopping point. The Strangler Fig approach keeps the application runnable by migrating inside-out with adapters at the seams between old and new technology.