the fundamentals behind palm key
Dependency Mapping
You cannot safely change what you cannot see.
The map
Programs, copybooks, JCL, data flow, CRUD — a legacy estate is a web no single person still holds in their head. Static analysis draws it in full: every caller, every file touch, every hidden connection, queryable by anyone.
The impact
With the map, "what breaks if we change this?" becomes a same-day lookup instead of a six-week study. Change stops being frightening, freezes thaw, and teams modify the system instead of tiptoeing around it.
The dividend
The map exposes what nothing calls and nobody uses — dead code, typically 33–40% of an aged estate. Retiring it before pricing is the cheapest scope reduction any modernization program will ever get.
dependencies · jcl · data flow · crud · 33–40% dead-code dividend