LEGACY .NET MODERNISATION
Legacy .NET Modernisation
Moving .NET Framework systems forward without a rewrite that never lands.
The rewrite that runs alongside the old system for two years and then gets cancelled is the standard outcome. Incremental migration is slower to describe and far more likely to finish.
Engagement profile
- First step
- Assessment, not code
- Method
- Incremental, always shippable
- Engagement
- Assessment, then retainer
- Old system
- Stays running throughout
01 What we deliver
Everything included in a production engagement.
- Written assessment of the existing system before anything is changed
- .NET Framework to .NET 8 migration, done in shippable stages
- Web Forms and legacy MVC moved to maintainable APIs and a modern frontend
- SQL Server to PostgreSQL migration where licensing is the driver
- Characterisation tests added around behaviour nobody documented
- Containerisation and a deployment pipeline to replace manual releases
How we engage
How an engagement starts.
Technical call
A working session, not a sales call. We go through what exists, what is breaking and what you actually need next. You leave with a straight answer about whether this is a good fit.
Written assessment
For anything involving an existing system, a short written document: what the architecture is, where the risk sits, and a recommended order of work. Fixed price, and yours to keep or hand to someone else.
Scope and terms
Scope, monthly commitment, rate and IP terms agreed in writing before work begins. Your repository, your infrastructure, your accounts.
Build and support
Weekly demos against a visible board. After go-live, support continues with the same person — there is no handover to a desk that has not read the code.
Frequently asked
Common questions about this capability.
Do we have to stop feature work while this happens?
No, and you should not. A migration that requires a feature freeze creates pressure to rush the risky parts. The approach is to move one bounded area at a time, keeping the system deployable after each step, so business work continues alongside it.
Nobody here understands the old system any more. Is that a problem?
It is normal and it is the reason the assessment comes first. Behaviour that only exists in code gets captured in characterisation tests before anything is touched — tests that assert what the system currently does, including the parts that look like bugs, so you find out deliberately rather than in production.
Should we move from SQL Server to PostgreSQL?
Only if there is a real reason — usually licensing cost or a hosting constraint. It is a genuine migration, not a configuration change: syntax, types, collation and any stored procedure logic all need attention. If SQL Server is working and paid for, the honest advice is often to leave it alone and spend the budget elsewhere.
How do you price something this open-ended?
The assessment is fixed price and delivered as a written document with a recommended sequence — it stands on its own and you are free to hand it to someone else. Migration work after that runs on a monthly retainer, because anyone quoting a fixed price for a legacy migration they have not yet looked inside is guessing.
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10 Next step
Let's architect the platform your business runs on.
About an hour, directly with the engineer who would do the work. We go through what exists, what is breaking and what you need next. No sales rep, no charge, and no retainer required to start — and if it is not a good fit for one person, you will hear that on the call.
- Who replies
- The engineer, not a rep
- First call
- About an hour, no charge
- Time zone
- UK & EU morning overlap