Agentic Method for Deterministic Validation of Legacy Code Migration
Summary
The paper introduces an agentic test-synthesis method called the Locksmith Loop to deterministically validate legacy COBOL-to-Java code migrations. It instrumentes COBOL and generated Java with mocks, runs an iterative witness-search loop and parity-preserving mutations to push coverage beyond input-based tests, achieving high branch coverage on case studies and deterministic parity with the COBOL reference.