Application modernisation without starting again
An old system that runs the business is an asset, not just a liability. Modernisation upgrades it in stages, so you get the speed, security and usability without the risk of a big-bang rewrite.
- Typical timeline
- 2 to 6 months
- Usually built with
- Next.js, TypeScript, Node.js
- You own
- Code, data and accounts, in your name
About application modernisation
Complete rewrites are the most common way modernisation projects fail. They take longer than planned, they must replicate years of accumulated rules that nobody wrote down, and the business gets nothing until the very end. We prefer to modernise incrementally: stabilise the current system, understand what it really does, then replace one part at a time while the whole continues to operate.
Signs your system needs modernising
Usually a good fit for
- Businesses running an application built years ago that is slow, fragile or unsupported
- Companies whose system depends on a technology or a developer that is no longer available
- Organisations with a desktop-only application that staff now need on a phone
- Businesses whose software cannot pass a client or partner security review
- Companies whose system works but cannot be extended without something else breaking
Signs it is time
- The application runs on a framework or runtime that no longer receives security updates
- It only works on Internet Explorer, on one machine, or on a server nobody wants to touch
- Adding a small feature takes weeks because the code has no structure or tests
- Performance has degraded as data has grown and nobody knows exactly why
- The original developer is gone and there is no documentation
Modernisation work we take on
Technical assessment
A written review of the current system: architecture, dependencies, security exposure, performance bottlenecks and the realistic options with effort estimates.
Incremental modernisation
Replacing the system module by module behind a stable interface, so the business keeps running throughout.
Interface modernisation
A modern, responsive, accessible front end over an existing backend, when the logic is sound and only the user experience is dated.
Database and performance work
Schema review, indexing, query optimisation and archiving strategy for systems that have slowed as data has grown.
Security hardening
Authentication, authorisation, dependency updates, input validation, secrets management and audit logging brought up to current expectations.
Cloud migration
Moving from a physical server or dated hosting to managed cloud infrastructure with backups, monitoring and a tested recovery process.
What's included in every modernisation project
- Documentation of what the existing system does, produced during assessment
- A phased plan where each phase delivers standalone value
- Old and new run side by side; we switch over one screen or module at a time
- Data migration with verification and a rollback path
- Automated tests added around critical logic before it is changed
- Responsive, accessible interfaces that work on modern devices
- Modern authentication, including single sign-on where required
- Monitoring, error tracking and structured logging added throughout
- Automated backups with restores tested, not assumed
- Handover documentation so future maintenance is not a rediscovery exercise
- 30-day bug-fix warranty after launch
Not included: third-party fees such as cloud hosting, database and backup storage, and licences for any software you keep or add. These are billed to you directly at cost and estimated in the quote.
Tools we typically use
Final choice made during scoping.
- Modern stack
- Next.jsTypeScriptNode.jsPostgreSQL
- Hosting
- DockerAWS or Azure
- Legacy systems we move from
- PHPASP.NET Web FormsAccess and Excel VBA
How a modernisation project runs
Typical timeline: 2 to 6 months, depending on scope and how quickly access and content arrive.
- 011-2 weeks
Assess and document
We map the current system's structure, dependencies, data and behaviour, including the undocumented rules that matter most.
- 021 week
Stabilise
Before changing anything we address immediate risks: missing backups, exposed credentials, unpatched dependencies.
- 033-5 days
Plan the sequence
A phased plan ordered by business value and risk, so the most painful problem is addressed first rather than the easiest.
- 044-16 weeks
Modernise in phases
Each phase replaces one area, is tested against the old behaviour and goes live independently, with a 30-day bug-fix warranty from its launch.
- 051-2 weeks
Migrate and verify data
Data moved with reconciliation checks proving the new system holds the same information as the old.
- 061 week
Decommission and document
The old system is retired only once the new one has run successfully, with an archive kept and documentation handed over.
Stuck with a system nobody wants to touch?
Start with a fixed-fee assessment: a written review of the system and a costed plan, with no obligation to continue.
How our fixed quotes and payments work →What modernising changes
What tends to happen, not a guarantee.
- 1
Risk spread across phases
Each phase is small enough to review and reverse, which is the opposite of a rewrite where everything lands at once.
- 2
The business keeps running
There is no period where the old system is gone and the new one is not ready.
- 3
Security you can answer questions about
Supported dependencies, proper authentication and audit logging make client security reviews straightforward.
- 4
Changes become affordable again
Once the code has structure and tests, a small feature takes days rather than weeks.
- 5
The system stops depending on one person
Documentation produced during assessment means the knowledge no longer lives only in someone's memory.
Should we modernise or rebuild from scratch?
It depends on how much of the existing system still reflects how the business works. If the logic is sound and the technology is the problem, modernisation is cheaper and far less risky. If the business has changed so much that most of the rules are now wrong, a rebuild may be more honest. The assessment gives you a documented answer with effort estimates for both, and you decide.
Can the business keep operating during modernisation?
Yes, that is the point of the phased approach. New components take over specific functions one at a time while everything else continues to run on the old system. Users often see improvements gradually rather than through a single disruptive switchover.
We have no documentation and the original developer has left. Is that a problem?
It is common and it is manageable. The assessment phase reconstructs how the system works from the code, the database and by interviewing the people who use it. That documentation is a deliverable in its own right and is valuable regardless of what you decide to do next.
How much does modernisation cost compared to a rewrite?
Phased modernisation usually costs less in total and much less before you see any benefit, because each phase delivers value on its own. A rewrite concentrates the whole cost before anything is usable. Every project starts with a fixed-fee assessment so you get a real number before committing to the larger work.
What if the old system is running on a server in our office?
That is a frequent starting point. We assess whether the priority is moving it to managed hosting for reliability and remote access, or modernising the application first. Often the hosting move comes first because it removes the immediate risk of a single machine failing with no tested backup.
Systems we often rebuild from spreadsheets and old software
Order Management System
One system tracking every order from enquiry to delivery, whichever channel it arrived through.
Inventory & Dispatch Tracker
Live stock positions across every store and warehouse, with alerts before you run out and a record of what left.
Employee Management Portal
Attendance, leave, documents, expenses and approvals in one place staff can reach from a phone.
Talk to us about application modernisation
Tell us what the work looks like today and what is not working. We will come back with what we think it involves, a realistic timeline and a fixed price.
The first conversation is free, with no obligation.