Legacy modernisation

Rebuild without stopping the business.

A legacy platform is usually the one making the money, so it cannot pause. We lock the current behaviour with tests, replace it in small verified cycles, and keep the old system serving users until the new one is proven, with the health score showing the improvement sprint by sprint.

See it in our work

At a glance

Starts with
A diagnosis on read only access
Rewrite or refactor
The diagnosis decides
Your roadmap
Features keep shipping, no freeze
Progress
Before and after scores, sprint by sprint

What it covers

Change the system without stopping it.

  • Diagnosis first

    Health score, debt density, hotspots ranked by how often they change and how bad they are. Numbers, not feelings, before any decision to rebuild or refactor.

  • Characterisation tests

    A safety net that locks what the system does today, so structural change cannot silently break it.

  • Strangler migration

    The old platform keeps running. Pieces move to the new one behind the same interface, and the switch happens when the numbers say so.

  • Stack moves

    ColdFusion to React, monolith to services, on premise to cloud, paid black boxes to open source monitoring.

How we do it

Lock the behaviour, then change it in small steps.

  1. 01

    Connect the repository, read only

    Thirty minutes to a diagnosis: architecture violations, complexity, test effectiveness, debt with a number and a trend.

  2. 02

    Lock behaviour before changing it

    Approval and characterisation tests on the parts about to move. Nothing structural changes until they are green.

  3. 03

    Small, test verified cycles

    Extract, test, commit, always green. Detection re scores after every push so the improvement is visible, not claimed.

  4. 04

    Run both, then switch

    Old and new side by side, traffic moved when the evidence supports it, and the old one retired when nothing depends on it.

What you get

A platform your team can run, the old one retired.

  • A diagnosis report with health score, debt density and a ranked fix list
  • Characterisation tests over the parts that change
  • A migration plan in small, independently shippable steps
  • Before and after scores, sprint by sprint
  • A new platform your team can run, and the old one retired safely

Where we have done it

Real engagements, named.

Questions

Questions we get asked.

Rewrite or refactor?
The diagnosis decides. Most systems are better refactored in place with a safety net; a few are cheaper to replace. We show you the numbers and say which.
How do you avoid breaking things?
Nothing structural changes until characterisation tests lock the current behaviour. Every cycle is small, tested and committed green. Detection verifies the fix after every push.
Can our team keep shipping features during this?
Yes. That is the point of small cycles and running both platforms. A freeze is what we are avoiding.

What clients say

In their words.

01 / 04

Life Insurance Direct
Before Metricsense, checking calls was a manual process: we selected files for review. Now the platform analyses every call, and we review by risk. It has identified customer experiences we would not have picked up before, and it lets us scale our quality assurance program without increasing headcount, with our team still the human in the loop. It helps us protect our customers, our business and our agents.

Russell Cain

Founder and CEO, Life Insurance Direct

Also under product development

Where it leads next.

All of product development

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