Eye4Tech

Home/Services/Legacy Modernisation

Make the system safe to change again.

The application still runs the business. The person who wrote it left, there are no tests, and every change is a risk. That situation is recoverable, and it does not require a rewrite.

Book a free consultation Send project details

Who this is for

Is this you?

  • Companies dependent on an application nobody fully understands
  • Teams on a framework or language version that is past end of life
  • Businesses that were quoted a full rewrite and could not justify it
  • Anyone whose system blocks a change the business needs to make

Problems it removes

What this fixes.

  • Every change carrying a real risk of breaking something else
  • A runtime or framework version that no longer receives security patches
  • Business rules that exist only in code nobody has read
  • No test coverage, so nothing can be verified before release
  • Hosting that cannot be moved because nobody knows what it depends on

Capabilities

What we build.

Deliverables, not adjectives. Each of these is something you receive and own.

System archaeology

A documented map of what the system does, what depends on it, and where the business rules actually live.

Safety net first

Characterisation tests around current behaviour, so a change can be proven not to break anything.

Incremental modernisation

Upgrade, extract and replace module by module, with the system live throughout.

Data migration

Schema and data moved with verification and a rollback path, not a hopeful cutover weekend.

Strangler replacement

New functionality built alongside, taking traffic gradually, until the old part can be retired.

How we approach it

The order we do things in.

  1. Assess before quotingA fixed-price assessment first: what is there, what is risky, and what it would cost. You own that document either way.
  2. StabiliseSecurity patches, backups, monitoring and version control before any feature work.
  3. Cover the critical pathsTests around the behaviour the business cannot lose.
  4. Modernise in slicesOne module at a time, released and verified, with the business running throughout.
  5. Document as we goThe documentation that did not exist is a deliverable of the work, not an afterthought.

Technology

What we work in for this.

PHPLaravel.NETPythonNode.jsMySQLSQL ServerDocker

Only what we support in production today. If your stack is outside this list we will say so on the first call rather than learn it on your project.

Custom Software E-commerce Integrations Automation & AI Cloud & DevOps

We have done this before

Related work.

KFC, Pizza Hut & Yum — Kenya · Quick-service restaurants · Delivery logistics

Built for one brand. Adopted by three.

The only endorsement an agency cannot write for itself: the client rolled the platform out to a second brand, then a third.

3brands running on one platform
Group leveladopted across brands
Real timebranch-network delivery visibility
Read the case study

Questions

Legacy Modernisation — the things people ask.

Should we rewrite it instead?
Almost never as a first move. A full rewrite means reproducing years of accumulated business rules — most of them undocumented — while the old system keeps changing. Incremental modernisation delivers value in weeks and carries a fraction of the risk. We will say when a rewrite genuinely is the right call, and it is rare.
Can you work on a system with no documentation?
Yes. That is the normal starting condition. The first deliverable of the engagement is the documentation that did not exist, and you keep it regardless of what you decide to do next.
What if the original developer is gone?
That is the usual situation. We read the code, the database and the production behaviour, and reconstruct the business rules from what the system actually does — which is often different from what people believe it does.
Will the business have to stop while you work?
No. The system stays live. We work in slices, behind flags, with a rollback path for each release. A cutover weekend is a last resort, not a plan.
How do you price this?
A fixed-price assessment first, because nobody can honestly quote a legacy system they have not read. The assessment gives you scope, risks and cost, and you are free to take it elsewhere.

Free consultation

Have a legacy modernisation problem you need solved?

Bring us the problem rather than a specification. A senior engineer will look at it and tell you how we would approach it — the likely shape, the risks worth knowing about, and a rough range.

Book a free consultation Pick a time now

Or email info@eye4tech.com — a senior engineer replies, usually within one business day.

Free · 30 minutes · no obligation

Free 30-minute technical consultation

  • A technical opinion on your website, application or infrastructure
  • A review of an existing project — what is solid, what is risky, what it would take
  • A second opinion on an approach or a quote you have been given
  • An honest answer on whether we are the right people, and what to look for if we are not
Book free consultation Send details