How to Improve Legacy and Business Applications without Expensive Modernization

Gartner defines a legacy application or system as an “information system that may be based on outdated technologies, but is critical to day-to-day operations.”

It’s common to see many businesses — and in a wide range of industries — rely on legacy apps for driving their operations. In fact, many of these applications were designed to support specific business functions, and they have been doing so for years (and in some cases, decades).

Today, these legacy apps are integral to how these companies run, but that longevity comes at a cost:

  • Reduced support in the market
  • Barriers to taking advantage of new features:
    • Data mining
    • Artificial Intelligence (AI)
    • Automation
    • Mobile interfaces
  • Increased difficulty in interoperability
  • Lack of integration with new tools

Fewer new IT graduates are well-versed in older programming languages, so if your legacy app uses antiquated code, you could have a lot of difficulty in finding capable developers to support it, and that difficulty will grow with each year.

In terms of interoperability, it’s increasingly difficult to make legacy apps work with strategic digital initiatives such as emerging applications, databases, APIs, portals, browsers and mobile technologies. This can be a problem when your staff is working on process automation, new business workflows, and self-service portals that require legacy system data. In which case, a whole layer of integration software may need to be created to allow the legacy business rules and data to be leveraged in the new workflows, portals and mobile.

Nine out of 10 IT decision-makers claim legacy systems are preventing them from harnessing the digital technologies they need to grow and become more efficient. – ComputerWeekly

When Replacing Your Legacy Application is Not an Option

Granted, the continued operation and maintenance of legacy applications is challenging. However, it’s also very challenging to push for a total replacement of one’s legacy apps. Not only is the upfront cost of a total replacement program expensive, but it’s also very high-risk from an operations standpoint.

In terms of the latter, businesses might be uncomfortable with the risk of service blackouts and productivity gaps resulting from having to reconfigure their systems and retrain staff for the new app. Likewise, the legacy app may be fulfilling a very specific function that can’t be replicated by a new application, at least not affordably or in a short period of time.

Alternatively, some companies might opt for a phased or incremental approach to replacing their legacy IT systems. In this case, they could opt to replace only a few of their legacy apps or even a subsection of legacy app features while still maintaining a legacy system overall.

Options for Supporting Legacy Apps

According to Docker COO Scott Johnston (via TechCrunch), businesses are spending as much as 80% of their IT budgets on supporting their legacy applications. Thus, legacy app support is common, especially from the standpoint of improving performance and maintainability.

By retaining — but also improving — your legacy app, you can improve your business operations outcomes without necessarily disrupting your staff or processes.

Below, we overview some of the common approaches businesses are taking to support as well as improve and modernize their legacy application assets.

Preserve Your Tried-and-Tested Business Processes
by Ensuring Your Legacy Apps Keep Working


Your ability to containerize depends on the characteristics of your specific legacy app (e.g. the programming language used to code it), but this is an increasingly used option.

Containerizing lets you maintain and deploy your legacy app much more efficiently. For example you can automate deployments across your organization. You can leverage capabilities such as rolling-back bad updates and managing patches/fixes without causing downtime to the system.

In effect, you can incorporate current IT development and operations practices into your legacy app without having to rewrite a single line of code.

In some cases, you can even begin leveraging microservices with your legacy app. Granted, it wouldn’t be as robust as a new app build from the ground-up, but you can use microservices to add new functionality to your app in containers (via new code in current languages).

Likewise, you can even improve the performance of your legacy app through containerization.

For example, KeyBanc added Node.js application servers ahead of its containered legacy app (which was written in Java). Doing so enabled KeyBanc’s app to handle increased mobile traffic and, in turn, enabled KeyBanc to future-proof its legacy app.


Rehosting is essentially the process of moving your legacy application to the cloud through the use of automated tools. It’s a prudent approach for companies planning to shift to the cloud, but still reliant on their legacy applications.

By rehosting hundreds of its legacy apps, GE Oil & Gas was able to reduce its TCO (i.e. total cost of ownership) by 52% without any other cloud optimizations (Amazon).


Replatforming draws from containerizing and rehosting. You can migrate your legacy application to the cloud and, in turn, replace specific app functionality with new alternatives.

For example, a company could opt to replace the database system of its legacy app with a new SaaS (i.e. software as a service)-based database (Amazon).

Through replatforming your legacy app, you can drive improvements in performance, scalability, and security without changing your entire app.

Leverage Application Management Services

Be it containerizing, rehosting or replatforming your legacy application, you require proven app development and maintenance expertise to implement the task.

You should leverage an application management services (AMS) provider who also has IT project delivery experience to spearhead legacy app improvement efforts at your company.

See Why Application Management Services Are Sought:

Granted, improving legacy apps is less resource-intensive than new app development, but even legacy app support requires knowledge in current technologies. Moreover, you need the experience to implement such projects without risking errors or other problems.

AMS providers bring the necessary knowledge and experience for improving legacy apps to the table. Not only does relying on an AMS provider free you from the costly and complex process of hiring and procurement to build-up internal capacity for implementation, but an AMS provider will also handle the long-term maintenance and support needs of your legacy app.

Getting Started

Resolute Technology Solutions brings over a decade of experience as an IT solutions provider for businesses in complex and highly regulated industries.

Utilize our application management services to implement your legacy app improvement efforts and to maintain your legacy apps to ensure that they perform optimally and securely. Contact us today to get started.



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