Big-bang ERP cutovers concentrate every risk into a single weekend. When they go wrong they go wrong across finance, operations and compliance simultaneously, and the rollback is usually theoretical.
A modular rollout inverts that. Pick the module with the highest pain-to-complexity ratio — often inventory or billing — and take it to production first, running alongside the legacy system for one reconciliation cycle.
The sequencing rule we use: never make a module live before its upstream master data is trustworthy. Most rollout failures we are called in to rescue are data problems wearing a software costume.
The trade-off is real: parallel running costs effort, and integration bridges you will eventually delete still have to be built properly. We think that is a good price for a programme where any single step can be reversed without a board meeting.
Working on something like this?
We are happy to review an architecture, sanity-check an approach or tell you honestly that you do not need an external partner for it.
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