Identifies the breaking changes between two versions of the SAME stack (e.g. .NET Framework 4.8 → .NET 8, Java 8 → 17/21, Spring Boot 2 → 3) that actually bite a given codebase, and drives the ecosystem's migration tooling. Use for same-stack uplifts, where code is preserved and tweaked — not rewritten from intent.…
Same-stack version uplift (e.g. .NET Framework 4.8 → .NET 8) — preserve the code, fix the version deltas, prove equivalence by running one test suite on both runtimes.