I Built a Desktop COBOL Migration Tool That Converts to 6 Modern Languages

A developer built Easy COBOL Migrator, a desktop transpiler that converts COBOL to six modern languages (C++17, Java 17, C#12, Python 3, Rust, Go) using a traditional compiler pipeline instead of LLMs. The tool addresses three key failures of AI-based migration: non-deterministic output, decimal precision loss in financial arithmetic (PIC/COMP-3), and inability to resolve COPY REPLACING across large codebases. The architecture follows a multi-stage compiler design—preprocessor, lexer, parser, semantic analyzer, and per-language code generators—running entirely offline.