Cloud-Native Application Development

Cloud-native application development on AWS for organisations carrying legacy weight.

MAP Lite
MAP
MVA
OLA
MMP
VMP

Re-architecture in chunks, migration from on-premises or another cloud, new cloud-native builds. AWS Advanced Consulting Partner with the Migration and Modernisation Competency. AWS funding applied where eligible: MAP Lite, MAP, MVA, OLA, MMP, and VMP.

The reality

The applications nobody would design today

Your application works. The business depends on it. That’s the hard part. The architecture decisions made a decade ago are now the reason every small change carries the weight of a large one. But the system is doing the job, and the case for change has to be made against that.

Our Cloud-Native Application Development practice exists for that conversation. Re-architecture in chunks rather than rewrites, sequenced to a horizon you can fund, with each piece releasable on its own.

The cost

Where the cost actually lives

Delivery

Release cycles that used to land each sprint now sit weeks apart. Features your product team wanted to ship months ago are still queued because the architecture won’t support them without a wider change.

People

Your senior engineers spend their time keeping the legacy estate alive rather than building anything new, and hiring becomes harder as the technologies in your stack drift further from what engineers want to work in.

Spend

On-premises hosting, third-party licences for technology that’s no longer the right fit, the operational overhead of an architecture that doesn’t scale on demand. The annual line is substantial, and the modernised version wouldn’t carry it.

Our approach

Modernisation is picking what to leave alone

A full rewrite bets the business on a single-shot delivery. Lift-and-shift moves the bill but solves nothing structural. The pattern that usually works for you is re-architecture in chunks, where the parts of your estate that are still working well stay where they are and the parts that are blocking the business get the work.

The architectural choices follow your workload. C# microservices on Amazon EKS where the strategic language and orchestration fit. Serverless on Lambda, Step Functions, and EventBridge where the workload’s event-driven. DynamoDB and Redis where the access pattern is key-value. The shape of the work is set by what your application actually needs, not by a default architectural template.

Method

How we approach it

1

Discovery, often AWS-funded

The Migration Acceleration Program (MAP Lite for smaller scopes, MAP for larger), the Modernisation Viability Assessment for Microsoft workloads, the Optimisation and Licensing Assessment for in-flight cost work, the Microsoft Modernisation Program for .NET, SQL Server, and VMware modernisation. We handle the application and compliance for the funding programmes so the funding actually lands.

2

Re-architecture in chunks

Each piece scoped to be releasable on its own. Your engineering team keeps shipping while the architecture moves underneath. Lower delivery risk, faster value, and easier to slot into your operating cadence than a multi-month freeze-and-rewrite.

3

Skills transfer alongside delivery

If your in-house team wants to upskill alongside the engagement, a joint build model puts our engineers next to your developers. If you want us to deliver and hand back, the model adapts. Either way, your team finishes equipped to keep building.

Outcomes

What changes for your business

Cloud Agility

A cloud-native AWS architecture where services scale on demand and deployments release without lengthy integration.

Capability Transfer

A modernised estate your in-house team has worked on alongside us, with the skills and confidence to keep evolving it, so your next change doesn’t need a fresh engagement.

Cost discipline

Services on AWS that scale with the work, instead of always-on legacy hosting; reserved instances and savings plans where the workload’s steady; serverless where the workload’s bursty. Your bill becomes something the team can see and reason about.

Engineering Focus

An engineering team back to building features rather than maintaining the past, which is usually the change your board case was about in the first place.

Proof

Where we’ve done this

A legacy on-premises estate, built on technologies nearly two decades old, modernised to AWS as a joint build with the in-house team. The core platform was re-architected from overnight batch into event-driven services on Amazon ECS.

“D55 are a highly experienced team that helped lead our business to push for and deliver an innovative and ambitious legacy to AWS transformation, with confidence.”Ed Berry, Head of Digital Products at Switch2

A bespoke cloud-native CRM and group operating platform on AWS, built Agile alongside the in-house team.

“D55 have helped to develop our CRM system and have been a valued partner in this process.”Andrew Bright, Director at ITP Energised

Migrationfrom Google Cloud Platform to AWS and modernisation of core services into C# microservices on Amazon EKS, with DynamoDB and Redis replacing the SQL Serverestate where the access pattern was key-value. The patterns we established continue to be used by the Tote team for each new microservice they add.

A legacy on-premises estate, built on technologies nearly two decades old, modernised to AWS as a joint build with the in-house team. The core platform was re-architected from overnight batch into event-driven services on Amazon ECS.

FAQ

Questions we get asked

How long does this typically take?

There’s no single answer. The discovery phase is usually weeks rather than months, especially when AWS funding applies. The delivery phase depends on what you’re modernising and which pieces are scoped first. The re-architecture-in-chunks model means your first releasable piece usually arrives in weeks rather than quarters.

Do you require us to commit to AWS?

The work is AWS-native and we’re an AWS Advanced Consulting Partner. The AWS funding programmes that reduce your upfront cost are AWS-only by definition. If your strategic cloud choice hasn’t been made, the discovery conversation includes that decision rather than presuming it.

How does this interact with our internal team?

Two models. Joint build, where our engineers work alongside your developers and the team finishes equipped to keep building (the Switch2 pattern). Or delivery-and-handback, where we build the platform and your in-house team takes it over at the end (the UK Tote Group pattern). The choice is yours.

How is this different from a large GSI?

Senior engineers on your work, not a junior team backed by a senior reviewer. Direct access to the engineer doing the work, not a tier-one ticket queue. The engagement is sized for the work, not for an enterprise programme management office.

Can AWS fund the discovery?

Often yes. MAP Lite, MAP, MVA, OLA, MMP, and VMP all apply to different shapes of work; we confirm eligibility for you in the intro call and handle the application work where it applies.

START A CONVERSATION

Let's explore the possible together

A short intro call, twenty to thirty minutes, to understand which door fits your situation: the Funded Data Strategy Diagnostic if your strategic plan is still being shaped, or a paid scoping engagement if your plan is already clear and the question is delivery.
solutions@d55.co.uk
+44 161 399 0257

Jonathan Rothwell,
CEO, D55