§ 01 — Notes
What migrations actually cost, what a cutover rehearsal finds, and how a lineage record survives an audit. Every note comes out of an engagement — no roundups, no predictions.
Featured · Data
A lineage diagram shows how the pipeline works today. An auditor asks how it worked on 14 March. Those are different questions, and only one of them is answered by a graph.
Showing 001–004 of 006
The programs are the last thing to read. Start with the job control and the copybooks, because that is where forty years of business rules were actually written down.
COBOL · Legacy · Mainframe · Code Archaeology
A 412-step runbook took 19 hours on its first rehearsal against a 9-hour window. By the sixth it took 6 hours 40. The rehearsals were not practice — each one was designed to fail differently.
Cutover · Runbooks · Migration · Rollback
Every legacy platform has interfaces that appear in no diagram and no register. Here is how we find them before cutover finds them for us — and why the interface diagram is the last place to look.
Integration · Discovery · Legacy · Cutover
A lineage diagram shows how the pipeline works today. An auditor asks how it worked on 14 March. Those are different questions, and only one of them is answered by a graph.
Lineage · Governance · OpenLineage · Audit
One note a month, when there is one worth sending
The same notes as above, in your inbox on the day they are published. We have never sent more than one in a month and do not intend to start.