Yesterday Anthropic announced Claude Code's COBOL modernization capabilities. It brought back something I built in 1987.
While at IBM Böblingen I wrote SCAN' (Semantic Code ANalysis Prime) — a VM/PROLOG prototype that automatically extracted control-flow from S/370 assembler programs, recognised structured blocks (If-Then-Else, Select, Loop), performed symbolic execution, and translated to a higher-level language. Then I had to transfer the prototype; IBM implemented it as ASMPUT (HLASM Toolkit Feature, 1995).
The mathematics behind it became US Patent 5,878,407 ("Storage of a Graph", IBM assignee, 1999): three indices per vertex enabling O(1) reachability queries by integer comparison alone.
The work has continued. There are two published successors (Springer FICC 2021, IntechOpen 2025) and an unpublished whitepaper on the structure and topology of arbitrary directed graphs — with direct application to symbolic execution and program debugging.
The full lineage is documented here: [https://gist.github.com/EnisOlgac/cba0451b9ef6fe7fd805b7b85f...]