Legacy Modernization: Migration & Re-platforming
Legacy modernization.
Move an ageing application or website onto a current stack incrementally (version upgrades or a full re-platform) without a rewrite that stops the business or a cutover date that slips.
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Framework and runtime upgrades done in steps that each ship (outdated React, an end-of-life Node or PHP, a database version past support) rather than one enormous jump nobody can review.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 the business never waits for a big-bang cutover that slips.
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
How it works
From first call to launch.
01
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.
02
Stabilize
Tests around the paths that matter, dependency triage, repeatable deploys. The system becomes safe to change before we change it.
03
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.
04
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.
Recent work
How we work on inherited systems.
This is method rather than metrics: we have not yet published a modernization case study, and we would rather say so than dress up numbers. What we can show is the approach applied inside other engagements: auditing and stabilizing inherited React and backend codebases before extending them, described on our frontend and backend pages. Ask on a discovery call and we will walk you through a real audit.
View Our WorkFAQ
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.
No. Slices move behind the same URLs with the old system still serving everything not yet migrated. Cutover is a routing change, not an outage window, and each step is reversible.
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.
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