Jun 18 2024

The Ultimate Roadmap to Modernizing Legacy Applications

There are many ways to give old software new computing power but following these steps can ensure a successful application modernization journey.

Modernizing an organization’s application portfolio has many benefits, including a better customer experience and lower costs for hardware and staff when it comes to application maintenance. However, many organizations struggle with how to get started.

IT leaders say they plan to spend 42 percent more on average on application modernization because it is seen as a solution to technical debt and a way for businesses to reach their digital transformation goals, according to the 2023 Gartner CIO Agenda.

But even with that budget allocated, businesses still face significant challenges, such as cost constraints, a shortage of staff with appropriate technical expertise, and insufficient change management policies to unite people, processes and culture around new software.

To successfully navigate the path forward, IT leaders need a strategic roadmap for application modernization. The plan should include prioritizing which apps to upgrade, aligning the effort with business objectives, getting stakeholder buy-in, mapping dependencies, creating data migration checklists and working with trusted partners to get the job done.

Here are the essential steps IT leaders should follow for a successful application modernization:

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Prioritize Apps to Modernize in Line with Business Objectives

First, organizations should conduct an assessment of their application portfolios to determine which apps are eligible for modernization, whether that be containerization, cloud migration, refactoring or another route. This can help IT leaders prioritize which apps to upgrade. It also gives teams a comprehensive picture of the entire application portfolio: performance, health, average age, security gaps, container construction and more.

Having an inventory of all of your applications can help you avoid duplicative investments and paint a clearer picture of how that application fits into your organization’s long-term strategy,” says Greg Peters, founder of strategic application modernization assessment (SAMA) at CDW. “By assessing the current state of applications and aligning them with business goals, organizations can prioritize modernization efforts based on their potential impact.”

For example, an organization hoping to reduce operational costs might prioritize moving legacy applications to the cloud, as this lowers data center expenses from the balance sheet.  

Once IT leaders have goals established, experts at Microsoft recommend assessing the financial and technical health of each application. From there, teams can finalize modernization plans for each workload and budget the resources required for success.

DISCOVER: The cloud is critical to modern applications in retail.

Get Stakeholders on Board Early

It’s also critical to get stakeholder buy-in from different leaders across departments, teams and users involved in the process. Doing so early on helps foster collaboration and minimizes resistance to change. Stakeholder involvement promotes transparency, enhances decision-making processes and ultimately increases the likelihood of successful modernization.

App Mod TOC


Map Data Dependencies and Where Data Will Reside

The next critical step is to map dependencies before beginning the actual modernization.

Even a minor change to the functionality of a core system can have major downstream effects, and failing to account for any dependencies on legacy apps slated for modernization can lead to system outages and business interruptions,” Hitachi Solutions notes in a post.

Taking this step is a smart way to “prevent potential disruption and ensure a smooth transition for end users,” Hitachi states.  

IT leaders also need to make sure that no data is lost when migrating legacy applications to new platforms. The same is true if teams are working to rewrite or transform the applications.

READ MORE: Learn about the tools businesses are using for application modernization.

“To prevent data loss when migrating applications from on-premises environments to cloud platforms, institutions should create checklists that detail how data needs to be migrated, how that data should be presented once it’s in the cloud and what testing needs to be done to ensure data accuracy,” Hitachi notes.

Select the Right Modernization Approach

At this point, IT leaders should decide which application modernization technique works best to upgrade their legacy software.

1. Rehost:

Also known as a “lift and shift,” rehosting allows the IT team to move applications from on-premises environments to the cloud with minimal changes. This quick migration is affordable and allows businesses to keep the core architecture of any app intact.

2. Refactor:

With this option, IT staff can rewrite portions of the application's code to optimize apps for cloud environments. This can improve overall performance in the cloud and make it easier to maintain.

3. Rebuild:

If the software requires an overhaul, IT may opt to rewrite the application from scratch while maintaining its original scope and specifications.

Greg Peters
Having an inventory of all your applications can help you avoid duplicative investments and paint a clearer picture of how that application fits into your organization’s long-term strategy.”

Greg Peters Founder of Strategic Application Modernization Assessment, CDW

4. Replatform:

With this option, an application is moved to the public cloud, but it is first overhauled to make it more like a cloud-native app, often via containerization.

5. Retain:

During a modernization effort, IT leaders may decide to leave some applications alone, especially those used by relatively few people.

6. Retire:

In some cases, IT leaders may decide that an application is no longer necessary and should be retired. This would involve disposing of software responsibly and stopping its renewal cycle.

7. Replace:

If it’s too hard to salvage old software, teams may opt to replace it entirely with new, commercial off-the-shelf products or a Software as a Service option. Often, the price of investing in a new tool is significantly cheaper than maintaining older software.

Each of these platform modernization approaches has distinct benefits, but all of them give legacy systems new computing functionality.

Solicit the Help of an Expert Tech Partner

Finally, no matter which route an organization decides to take when it comes to modernization, IT leaders should partner with trusted third parties to complete the work. Tech experts can help create roadmaps that are tailored to the organization’s business objectives and financial and technical capabilities.

“Organizations may find it helpful to work with a trusted third-party adviser when conducting assessments, especially if they have limited technical resources,” Peters says. “Having an outsider’s point of view can also help appropriately rank and prioritize applications.”

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