Legacy System vs Modern System: How to Know When It’s Time to Move On 

Legacy systems like ColdFusion apps, Delphi codebases, or even Lotus Notes might still be running, but for how much longer? If your organisation is facing performance issues, security gaps, or rising maintenance costs, it’s time to ask yourself: 

“Is our system helping the business grow or is it holding us back?” 

In this blog, we’ll go through the differences between legacy and modern systems, how to assess where your software stands, and what options you’ve got to get your organisation future ready. If you’re not sure if your system is still fit for the future, a great place to start is our quick quiz: 

Take the Legacy Modernisation Scorecard Quiz

What Is a Legacy System?

We have a few blogs covering what legacy systems are, but we’ll briefly go over it here too. A legacy system is software or infrastructure that’s outdated, technically or functionally, but still in active use. It might be built on unsupported languages, rely on on-premise infrastructure, or isn’t compatible with modern platforms like Angular, cloud-native environments, or CI/CD pipelines. 

Why Do Systems Become Legacy? 

There are several reasons systems become outdated over time: 

• Unsupported technology: Built on frameworks or languages no longer maintained 
  

• Misaligned with current business needs: Systems that no longer reflect how the organisation operates 
  

• Knowledge silos: When only a few individuals understand how the system works 
  

• Lack of documentation: Making future updates complex and risky 
  

• Avoidance of change: Concern over downtime, cost, or disruption 
  

These issues accumulate, making the system more fragile and harder to maintain. 

Common Legacy Platforms 

ColdFusion  

ColdFusion used to be the go-to for web app development, but it’s quickly becoming a liability. With Adobe announcing major deprecations and removals in the upcoming ColdFusion 2025 release, many businesses relying on legacy ColdFusion apps could soon face serious disruptions. 

Key features that will be affected include: 

• Classic ColdFusion Administrator UI - Removed entirely and replaced with the new Modular Admin interface. 
  

• cfdocument, cfchart, and cfreport tags - Deprecated. These core tags for document generation, reporting, and charting are being phased out and may be removed in future versions. 
  

• Java-based PDF generation - Deprecated. Older PDF engines are being replaced by modular PDF services. 
  

• Built-in ColdFusion Web Server - Deprecated. Adobe recommends transitioning to external web servers such as Apache or IIS. 
  

• ColdFusion as a Service (CFaaS) - Deprecated. Built-in endpoints are being replaced by modular services for improved flexibility and scalability. 
  

These are fundamental changes that could cause critical parts of your app to stop working entirely if you upgrade and leave you vulnerable if you don’t. 

On top of that, ColdFusion is no longer widely used: 

• The developer pool is shrinking, making maintenance expensive and slow 
  

• Hosting options are limited, especially in modern cloud environments 
  

• It’s increasingly difficult to integrate ColdFusion apps with modern systems and tools 
  

Delphi

Delphi was once a popular language for building Windows applications, especially in industries like manufacturing, logistics, and engineering. But, due to it becoming a legacy technology, continued reliance on Delhpi can cause issues for your organisation  

While modern versions of Delphi still exist, many organisations are running older versions (Delphi 5, 7, or XE) that are no longer supported or compatible with current operating systems and frameworks. This leads to several challenges: 

• Increased maintenance costs, as support for outdated libraries and dependencies disappears 
  

• Incompatibility with modern development environments, cloud infrastructure, and CI/CD pipelines 
  

• Growing security risks, due to outdated code and limited patching options 
  

• Knowledge silos, with only a handful of developers still familiar with legacy Delphi systems 
  

Even if your Delphi application is still working, it could be tied to outdated hardware, lack documentation, and might not be easily scalable or integrated with modern tools. 

Lotus Notes 

Lotus Notes (also known as HCL Notes) was a widely used platform for email, collaboration, and custom business applications. But now it’s considered a legacy solution. One that’s difficult to maintain and even harder to modernise without a clear strategy. 

Many businesses still rely on Lotus Notes for business critical workflows built years or even decades ago. However, they now face growing issues: 

• Poor user experience, especially compared to modern platforms 
  

• Limited integration capabilities with cloud-based tools and APIs 
  

• Difficulty retaining talent, as fewer developers want to work with Notes 
  

• Increased pressure to modernise, as vendors phase out support 
  

While Lotus Notes still offers extended support many third-party tools and integrations have been discontinued, and even supported versions may not meet today’s security or compliance requirements. Upgrading to a newer version often comes with significant licensing costs and still doesn't solve the core problem: the architecture is outdated. 

When Is the Right Time to Modernise? 

You'll know it’s time to modernise when you see these warning signs: 

• Frequent performance issues or downtime 
  

• Frustrated users and productivity slowdowns 
  

• Security or compliance concerns 
  

• Expensive or delayed updates 
  

• Trouble integrating with modern systems or SaaS tools 
  

These aren’t just IT headaches but strategic risks! 

What Are My Options? 

Don’t worry, you don’t always have to do a full rebuild! We have other blogs that go in-depth on the options (check them out here), but here’s a brief overview: 

Take the First Step 

Modernisation doesn’t need to be overwhelming. If you’re not sure where your system stands, our quiz can help you out. 

In just 5 minutes, it helps you: 

• Evaluate your system’s current state 
  

• Identify key risks and opportunities 
  

• Receive practical, next-step recommendations 
  

👉 Take the Legacy Modernisation Scorecard Quiz!