Legacy Modernization: Migration & Re-platforming

Legacy modernization.

Move an ageing application or website onto a current stack incrementally, whether that is version upgrades or a full re-platform. Each slice ships on its own, so the work does not depend on one cutover date holding.

What the work involves

Modernize without stopping.

Audit before anything moves

A read of the codebase, dependencies, infrastructure and the parts everyone is afraid to touch, so the plan is based on what is actually there, not what the documentation claims.

Stabilize first

Before migrating anything we make the current system safe to change: tests around the critical paths, the worst dependencies patched, deploys made repeatable. Migrating an unstable system just moves the instability.

Version upgrades

Framework and runtime upgrades done in steps that each ship (outdated React, an end-of-life Node or PHP, a database version past support) rather than one enormous jump nobody can review.

Incremental re-platforming

Move to a new stack a slice at a time, running old and new side by side behind the same URLs, so value arrives during the work rather than waiting on a single cutover date.

Data migration

Schema mapping, backfill, and reconciliation you can verify, with a rehearsed rollback, because the data is the part you cannot recreate.

Performance and accessibility recovered

Modernization is the moment to fix what accumulated: Core Web Vitals, WCAG compliance, and the mobile experience that was bolted on afterwards.

Our stack

JavaSpring BootReactNext.jsTypeScriptNode.jsPostgreSQLMySQLWordPressCI/CD pipelines

How it works

From first call to launch.

  1. Audit

    We read the system as it is: code, dependencies, infrastructure, and the failure modes your team works around. You get a written assessment and a risk-ordered plan.

  2. Stabilize

    Tests around the paths that matter, dependency triage, repeatable deploys. The system becomes safe to change before we change it.

  3. Migrate in slices

    One slice at a time, old and new running together, each step shipped and reversible. No date where everything moves at once.

  4. Cut over and retire

    Traffic moves fully, the old system is decommissioned deliberately rather than left running "just in case", and your team gets the handover.

Our approach

How we work on inherited systems.

Method rather than metrics. We have not published a modernization case study, and we would rather say that than dress up numbers. The two builds we have published, a connected health platform for Seniorsoft and Alpine Goats Farms, are written up in full and show how we audit, test and ship, which is the same discipline this work runs on. Ask on a discovery call and we will walk you through an audit.

Read the Case Studies

FAQ

Common questions

Almost never, and we will argue against it. A full rewrite means months with no shippable value while the old system still needs maintaining, and it usually rediscovers requirements the hard way. We migrate incrementally (old and new running side by side, each slice shipped) so value arrives throughout and you can stop at any point with a working system.

The method is built to avoid it. Slices move behind the same URLs with the old system still serving everything not yet migrated, so cutover is a routing change rather than an outage window, and each step is reversible. Where a step genuinely cannot be done live, usually a database migration, we say so in the plan and schedule the window with you instead of discovering it on the night.

That is the normal starting position, and it is exactly why the audit and stabilize phases come before any migration. We characterise the current behaviour with tests first, and that becomes the specification the new system has to match, which matters when nobody can tell you what it is supposed to do.

Often that is the right call. If the architecture is sound and only the versions are out of date, a staged upgrade of framework, runtime and dependencies is far cheaper than re-platforming. The audit tells us which of the two you are actually looking at.

Schema mapping and backfill are planned as their own workstream, with reconciliation you can check and a rehearsed rollback before anything runs against production. Code can be rewritten; data usually cannot be recreated.

The audit is a fixed, standalone engagement: you get the assessment and plan whether or not you continue with us. Migration work is then quoted against that plan, slice by slice, so you are never approving a number based on guesses about a system nobody has read yet.

Contact

Stop explaining your value. Start showing it.

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