Top Companies Offering Application Modernization Services

A lot of enterprise software still running today was built long before anyone talked about the cloud. Patches pile on top of patches. A two-line change takes a month to ship. And the people who read COBOL fluently are retiring. Meanwhile, the support bill grows every year, mostly just to keep things running. That’s why companies move to the cloud, and it has far less to do with hype than with that invoice.

Refactoring or Rearchitecting? Picking a Modernization Path While the Business Keeps Running

Here’s where many projects go wrong. Someone picks a strategy at the kickoff meeting, and nobody has checked yet which parts of the app the business actually uses day to day.

Refactoring is the gentler route: tidy up the code, rip out the framework from 2012, pack everything into containers and push it through a CI/CD pipeline onto AWS, Azure or GCP. Users won’t notice a thing. Honestly, they shouldn’t. The monolith, though, is still a monolith when the dust settles.

Rearchitecting means taking the app apart. Billing turns into one service, inventory into another, notifications into a third, each with its own little database, and all of it usually sitting on Kubernetes. One team can ship on Tuesday while another is still testing. The price? Months of design work and plenty of arguments over APIs.

So which one? A billing engine whose logic hasn’t changed in ten years rarely needs microservices. Refactor it and move on. A customer platform that marketing wants updated every week is a different story. And a Mainframe to Cloud move tends to drag rearchitecting in, planned or not.

And downtime? The strangler fig pattern takes care of most of it. New services take over one function at a time while the old system keeps working next to them. Nobody has to flip a giant switch on a Sunday night and hope for the best.

Top Modernization & Enterprise Software Transformation Firms

Accenture

Accenture is on nearly every enterprise shortlist. It has separate business groups for AWS and Google Cloud, plus Avanade, its joint venture with Microsoft, so the target cloud is rarely an issue.

GenWizard, its generative AI platform, chews through legacy code and speeds up conversion. Teams are big, and so are the contracts. It fits multi-year programs where strategy, engineering and change management all report to one owner.

DXC Technology

DXC Technology starts with the whole portfolio, sometimes hundreds of apps, and sorts each one into a pile: rehost, rearchitect or swap for SaaS. Advisory, mainframe migration and the company’s modernization factory are described at https://dxc.com/solutions/application-services/applications-modernization.

The numbers speak for themselves. Around 65,000 workloads are transformed every year, and automation cuts application costs by 30%, according to the company. ISG ranks DXC as a Leader in Application Modernization in the US and Europe. One example: KION Group lowered its IT infrastructure costs by 25% after moving to Azure with DXC.

Kyndryl

Kyndryl was IBM’s infrastructure services business until the 2021 spin-off. Mainframes aren’t a niche topic here. That’s the company’s bread and butter.

Plenty of banks have no plans to unplug the mainframe, and Kyndryl works with that. Old systems get hooked up to AWS, Microsoft or Google Cloud through APIs, while Kyndryl Bridge gives the ops team one screen for the whole hybrid mix.

IBM

IBM Consulting brings the people and, quite often, the platform too. Red Hat OpenShift on one side, IBM Z on the other, and Z still runs the core ledgers at a lot of banks and insurers.

Sitting on a few million lines of COBOL? watsonx Code Assistant for Z uses generative AI to do the first pass at turning them into Java. For regulated firms that would rather not leave Z in one jump, that’s usually where the conversation starts.

Cognizant

Cognizant, out of Teaneck, New Jersey, takes on the whole job, from figuring out what an old app even does to rewriting code, opening up APIs and landing workloads on AWS, Azure or GCP.

Its Flowsource platform brings AI into everyday engineering work. Banking, insurance and healthcare are where Cognizant is most visible. In those sectors, one note from an auditor can hold up a release longer than any bug.

Capgemini

Paris-based Capgemini brings Capgemini Engineering and Sogeti into its modernization projects. Some clients want a quick lift-and-shift. Others need a full microservices rebuild with CI/CD and DevSecOps built in. Capgemini does both.

Data that legally can’t leave the EU? That’s where the company often makes the shortlist. Alliances with AWS, Microsoft and Google Cloud, along with deep SAP experience, help too.

Counting the Real TCO of a Legacy App Before a Migration Project Starts

Ask an IT director what the legacy system costs, and the answer is usually the hosting invoice. That’s maybe half the picture. Often less.

Start with the obvious stuff: servers, mainframe MIPS, data center rent, licenses, support contracts. Then add the people, including that one COBOL contractor who names a price (and gets it). Then the risk, meaning outages, patches nobody can install and whatever the last audit dug up. And then the quiet one: features that never shipped because the team was busy babysitting old code.

Put three to five years of all that on one line. The second line is the new setup, with cloud bills, someone to run Kubernetes, the migration itself, training and a few awkward months of paying for both systems at once. Where the two lines cross is the payback point. Sounds simple, right? It rarely is. Hidden costs almost always sit in the people and risk lines.

Final Thoughts

There’s no universal winner. Accenture and DXC Technology make sense for large portfolios that need factory-scale delivery. IBM and Kyndryl are a safer bet when the mainframe isn’t going anywhere. Cognizant and Capgemini do well in regulated industries. Honestly, though, the vendor matters less than the homework. Pick the strategy and count the TCO first. Then start making calls.

FAQ

How long does modernization usually take? One app? Three to six months for a refactor. A full mainframe or portfolio program runs 18–36 months, in phases.

Is rearchitecting always the better choice? No. It pays off when an app changes often and needs to scale. For stable systems, refactoring is cheaper and less risky.

Can it be done without downtime? Mostly, yes. Phased cutover, the strangler fig pattern and running old and new systems in parallel keep the business going.

Which cloud is best for legacy apps? AWS, Azure and GCP all handle mainframe migration and Kubernetes. The deciding factors are usually existing licenses, team skills and where the data has to live.