Re-engineering legacy software has become a major concern as application life cycles become shorter.

Flexera research suggests that the average application lasts for around five years before it reaches its EOL/EOS. This means that increasingly IT systems are becoming legacy systems without vendor support.

Low code is one of the hottest legacy modernization trends. In this article, we will look at how low code can help in your legacy application modernization needs.

What is Legacy Software?

Legacy software is any application or code that has been

  • Around for a few years
  • Serves an important business purpose
  • Uses technologies that cannot support your current requirements.

For example, many large banks use mainframe-based backends for day-to-day transactions. These systems are not compatible with today’s cloud-based, multi-platform applications.

Why Do I Need To Modernize My Legacy Systems?

Here is why you should not ignore the need to change your legacy system:

Business Risk

Your competitors may use newer and better technology to offer richer UX at a lower cost. For example, fintech startups can attract mobile-first audiences through faster and better mobile apps, which banks are finding harder to replicate.

Lack of Functionality

Legacy applications are often incompatible with newer requirements. Users have to make do with poor workarounds or, in the worst case, nothing at all.


You will often need to build custom security patches for your legacy systems yourself because they might be built on software that is no longer supported by their makers (for example, legacy systems that use Internet Explorer will no longer get automatic security updates from Microsoft after Jun ’22). Moreover, you will have to choose poorer security architecture because your legacy system is incompatible with newer hardware.

Hiring Costs

Software experts who can work on legacy applications command a premium because it is a rare talent.

Regulatory Compliances

Regulatory compliances such as GDPR, SOX, HIPAA, and KYC requirements are becoming stricter. It is hard to mold legacy applications to suit these needs.

Software Support

If the original vendor no longer supports the legacy system, you will need to create patches to fix bugs and vulnerabilities on your own.

The cost of maintenance is also very high. For example, ten legacy systems in the US federal government that need modernization the most cost the government ~$337mn in 2019.

Why Legacy App Migration is Challenging

Here are some reasons why businesses keep putting off legacy app migration:

  • Any migration will result in downtimes and disruptions to a running business.
  • Data migration is complex and can lead to data loss. Businesses avoid data migration because legacy data holds a wealth of information they don’t want to touch.
  • Scope Creep, or solving unforeseen problems arising from legacy code changes.
  • Lack of documentation and complex coding structures in legacy applications make it difficult to transition functionality to newer code.
  • High costs of licensing and customizing new technology.
  • Difficulty in finding vendors who specialize in legacy migration or the cost of having to train your existing IT team to migrate your applications

Legacy Migration Strategy with Low Code

There are three main strategies that you can use to modernize your legacy systems:

Replace completely

Replacing legacy code lets you build a new system from scratch. You can bring in:

  • New architecture
  • Newer technologies
  • Better efficiency
  • Better customization

On the flip side, this strategy involves high costs and disruption. Low-code solutions let you build new code quicker, ensuring fewer disruptions and lower costs to hire and train software developers.

Migrate to a new platform

You might have a legacy application that works perfectly fine on a desktop, but you need it now on mobile or the cloud.

Here, the key challenge is a smooth transition and zero disruptions to business. Low code enables a cloud-based, cross-platform approach to migration with centralized management and built-in APIs and integration tools that help connect new architecture to legacy code.

Extend functionality

This is a gradual approach to integrating with newer platforms and adding new features. This approach ensures minimal disruption.

However, this is a time-taking and iterative approach. Here, low code helps quicker development with reusable components that reduce the time to develop new functionality extensions.

Steps to Rewriting Legacy Applications Using Low Code

Legacy modernization has gone beyond these three boxed-down approaches and is typically a hybrid of all three. Let us look at how migration works in practice, and how low code can help.

Identify what needs to be changed 

It is important to break down your legacy system into bite-sized pieces to understand which of them you can reuse, which ones you can adapt, and which ones you should discard completely.

Extend existing capabilities

From the identified pieces, isolate the ones that need to be enhanced.

Low code can help develop extendable and platform-independent applications that keep your old code intact while improving its capabilities/features.

Data migration is a good example of legacy modernization, where low code does this brilliantly. Instead of ripping out data and plugging it into a new platform, it lets you build cloud-ready applications that work atop legacy data systems, providing a much better UX to the customer.

Create new applications to replace the dead parts

If certain pieces of the legacy system need a complete replacement, low code can help you replace them through quickly yet robustly built applications. You can keep sunsetting applications as newer ones come online without disturbing existing functionality or user experience.

Benefits of Using Low Code Platforms for Legacy Transformation


The drag-and-drop-based visual approach of low code lets coders move quickly to build new applications. It also lets citizen developers create quick prototypes to show what they need, making requirements gathering faster and better.


Application modernization used to be a time-consuming, slow and costly affair. Low code development provides reusable modules that connect logically and consistently.

You need to make changes only when you need specific customizations, and most coding grunt work gets automated.


Reusable code means lower complexity and better quality. It reduces the chances of error since the code has already been tested and proven.

Low code is your best bet if your application modernization requires similar modules to be replaced in multiple places.


If you plan to replace even a part of your legacy application, your migration strategy will involve either buying an off-the-shelf product or building a custom one.

Both approaches can be very costly, but with low code, you can significantly reduce the cost of building a custom solution.

Avoiding scope creep

Scope Creep is inevitable during legacy transformation. Low code helps overcome scope creep by reducing development time to make fixes for features that break when you are trying to modernize another component.

Final Words

Legacy application modernization services from low code applications are helping businesses migrate to newer and better platforms with lower risk of disruption, reduced development time, and lowered costs.