Product engineering
Legacy system modernisation
Legacy modernisation is the incremental replacement of ageing software with maintainable systems, without a big-bang cut-over and without losing data. Hexploits does it by documenting what exists, wrapping it in tests, and replacing it piece by piece while the business keeps running.
A named engineer replies within one working day. A written scope and an indicative price within two.
Who this is for
- Businesses whose core system runs on a platform, language or supplier that is no longer supported.
- IT directors who cannot get a change made without a month of risk.
- Finance directors paying licence and hosting costs for systems nobody will touch.
What you get
Deliverables, not slogans. Each one appears in the statement of work.
- An assessment: architecture, data, dependencies, risks and a modernisation route with options and costs.
- A test harness around the existing system so that behaviour is captured before anything changes.
- Incremental replacement with the old and new running side by side and reconciled.
- Data migration rehearsed and verified.
- Decommissioning of the old system with evidence.
Our engineers work across the major languages, frameworks and cloud platforms. We build on the stack you already run, with technology choices explained in writing before work begins.
How it is delivered
The same four stages as every Hexploits engagement, applied to this capability.
Stage 1
Assess
Two to four weeks to understand what the system does, who depends on it, and where the risk is. Output: a written route with options.
Stage 2
Stabilise
Backups verified, documentation written, tests added, so change becomes safe.
Stage 3
Replace incrementally
One capability at a time moves to the new system; both run in parallel until the numbers match.
Stage 4
Decommission and operate
The old system is switched off with a rollback plan, and the new one goes under managed support.
How success is measured
Every engagement agrees its measures and the measurement period in writing before work starts.
- Time and risk to ship a change, before and after.
- Licence, hosting and support cost of the retired system.
- Incidents and downtime during the migration (target: none visible to users).
Proof
Case studies with numbers, and reviews linked to Google where they were left there.
Gradvisor · Charity · 8 weeks to production, then ongoing
98% faster page loads and a 12% smaller cloud bill for a UK careers charity
swarmd.ai · Software vendor · 6 months
Enterprise AI control plane delivered in six months at 75% under budget for a UK software vendor
Director, Gradvisor
“Fantastic company and our development partner for Gradvisor, a social mobility careers platform with national ambitions. Extremely responsive and mission-oriented. Cameron owns any shortfalls humbly - rare for IT providers. Thinks like a client too.”
Director, Lothbury
“Top quality delivery, and reasonable price. Will be using again.”
Questions we get asked
Do we have to stop using the system while you rebuild it?
What if there is no documentation and the original developers have gone?
Can you take over a system someone else built and just run it?
Related
Sectors where this is most often needed
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Next step
Request a proposal.
Tell us about the system and the sector. A named engineer replies within one working day. A written scope and an indicative price within two working days of a short scoping call.