Legacy System Modernisation: Proven Guide to Avoid Risk
The four routes out of a legacy system are well known — rehost, refactor, rebuild or replace — and the wrong one gets chosen more often than not, usually because the decision is made on temperament rather than evidence. This guide works through what modernisation actually means, the four options in detail with the conditions each one suits, a six-factor scoring model that turns preference into a defensible ranking, what each route costs in money and elapsed time, how to sequence delivery with the strangler fig pattern so the business keeps running, and the failure patterns that sink modernisation programmes.
