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From Custom / bespoke software

Migrating from an in-house custom system

For firms who commissioned a custom platform in the 2010s and are ready to modernise without commissioning another one.

High effort 10–16 weeks Firms with custom-built legacy software

The decision framework

Custom systems are typically retained past their useful life because the cost of moving feels enormous and the current system 'still works'. The right question is not the migration cost but the ongoing maintenance liability. Custom systems accrue technical debt indefinitely; commercial platforms absorb it.

Data extraction

Every custom system is different. Our migration team spends the first 1–2 weeks reverse-engineering the schema and building a customer-specific extraction script. Direct database access (read-only) is typically required.

Preserving history

Custom systems often contain 10+ years of history that no commercial product natively models. History migrates as structured notes on each case, timestamped with the original date. This preserves the record without forcing awkward retrofitting into a modern schema.

User re-training

Users of custom systems have highly specific muscle memory. Budget more training time than for any other migration path: two full team training days and a four-week 'guided operation' period with weekly Q&A.

Decommissioning the old system

After cutover, run the legacy system in read-only mode for 6 months for historical access, then archive to PDF + document store, then decommission. The infrastructure cost savings alone typically pay for the migration.

Ready to plan your migration?

Our onboarding team runs the migration for you as part of your Practice plan. Book a scoping call.