ProAg shifts legacy .NET Framework 4.8 process in 5 weeks with AI

ProAg's legacy estate is typical of specialty insurance: more than a decade of business logic accumulated in Windows-only .NET Framework libraries, with hundreds of processes to move. The internal team's pace of over six months per process implied a multi-year program, which is why the company brought in an outside partner and targeted one of the hardest processes rather than an easy one.

The choice of the hardest process appears deliberate: a success on a trivial task would not answer whether the method works on the work that actually has to be done. The architecture also had to clear a regulatory bar first—US crop insurance is heavily regulated, so the team ran Claude via Amazon Bedrock inside ProAg's own AWS account, keeping every model call under existing controls.

The technical sequence matters as much as the speed. Before code was touched, agents mapped dependencies into a graph that subject-matter experts reviewed, and a separate agent drafted a migration plan that flagged Windows-only libraries for replacement or rewrite. Migration then proceeded stage by stage, with a validation harness built alongside the migration rather than after it, so mismatches could be localized early. A final field-level comparison on production-like data became the formal evidence ProAg keeps. The public case is explicit that this does not mean production readiness without further hardening, so the five-week figure should be read as a pilot result—the reusable parts being the harness, documentation steps, and agent templates.