Legacy modernization strategies and approaches for 2024

Jerzy Zawadzki - Chief Technology Officer
7 minutes read

The only constant in software is change. Projects evolve over time, and software should adapt accordingly. It doesn't always go this way, though. Often, applications become stuck in their original form, turning into what we know as “legacy systems”. These systems, while functional, may not align with current technologies or business processes, and thus suffer often from issues like outdated code or lack of support.

So, what to do about them? This article explores a few legacy application modernization approaches and strategies condensed into a set of best practices.

What is legacy application modernization?

Legacy application modernization refers to the process of transforming outdated software systems into scalable, efficient, and secure platforms.

IT legacy systems are often characterized by outdated languages, architectures, methodologies, lack of tests, and difficulty in understanding and modifying the code. Usually, a software modernization plan involves updating the underlying technology, rearchitecting the system, or, in some cases, even replacing it with a more modern solution.

Why does legacy software modernization actually matter?

Why legacy systems modernization is essential for modern businesses? There are several reasons:

#1 Remaining relevant despite rapid technology evolution

Nowadays, technology evolves not even by the minute, but by the second. Staying relevant means keeping your systems updated. Modernizing legacy applications bridges the historical gap so that your business can meet modern demands and become future-proof. The future is digital, and modernization ensures you're not just ready for it, but already there.

#2 Unlocking new avenues of growth

Modern systems can adapt and scale as your business grows. They're designed to handle increased loads, new types of data, and emerging business models, to turn potential obstacles into stepping stones for growth.

#3 Enhancing security = ensuring compliance

Outdated applications can be a playground for security breaches. Legacy code can lead to slow feature development, increasing bugs, fragility, difficulty in hiring new developers, and rising infrastructure costs. Modernization of IT legacy systems isn't then just an upgrade, but a necessity for protecting your business data, and providing compliance with current security standards.

#4 Streamlining operations for improved efficiency

Clunky, outdated software slows your business down. Modernization streamlines your operations, automates repetitive tasks, and frees your team to focus on innovation rather than maintenance.

Best legacy application modernization strategies

To take the right approach to modernizing legacy applications, you can bet on several strategies that will help you deal with the complex process of updating and upgrading legacy systems. All techniques matter, but some of them will become more valuable than others for your business. So, what can you do?

Prioritize continuous updates

“Prevention is better than cure”, as the saying goes. This means that regularly updating code and dependencies is really important yet often overlooked. Many companies opt to maintain older systems as long as they function, only to realize later the magnitude of the change they had initially postponed. A prime example of this is good, old Microsoft Windows legacy. Following each announcement of “end of support”, countless companies worldwide find themselves left with outdated Windows systems that require urgent upgrades. But they wouldn’t be in that situation if they actually prioritized updates.

This practice helps in keeping the application aligned with current technologies and reduces the risk of it becoming a legacy system. ​​Regular updates mean your software stays compatible with new technologies and, at the same time, avoids becoming outdated.

Supervise architecture

In legacy application modernization processes, supervision ensures that growth and changes in an application's architecture are meticulously monitored and guided. A clean, efficient, scalable, and adaptable architecture always requires such supervision. That is, unless as a company, you want your architecture to become unwieldy or diverge from its intended path. Monitoring merges a continuous oversight process in which architectural decisions are made with a long-term vision in mind. Current functionality equals future adaptability.

You can do this via:

  • Conducting periodic assessments to double-check if the architecture aligns with all business goals and requirements.
  • Implementing industry-standard best practices and design principles to maintain architectural integrity.
  • Maintaining a flexible architecture that can accommodate growth and changes without significant reworking being required.
  • Identifying and mitigating potential risks associated with architectural changes.

This approach aims to create an application architecture that not only meets today's demands, but is also flexible enough to adapt to tomorrow's challenges.

Maintain proactive technical debt management

Building on the concept of continuous updates, actively managing and reducing technical debt is another key aspect.

This involves activities such as:

  • Timely refactoring of problematic code areas
  • Steering clear of shortcuts that might lead to more complex issues down the line
  • Maintaining a cleaner, and more efficient codebase, which in turn facilitates easier updates and integration with new technologies

The longer it's left unattended, the more challenging and costly it becomes to resolve. And the numbers speak for themselves here: studies reveal that engineers spend about 33% of their time addressing technical debt, with organizations losing 23%-42% of their development time. Furthemore, according to a McKinsey study, companies estimate their tech debt costs to exceed even $2 billion across all of their systems and applications. There's a lot of money at stake.

Embrace change with Agile practices

At the heart of agile is iterative development – an integral part of modernizing legacy systems.

Agile methodologies focus on flexibility, collaboration, and responsiveness to change. The modernization process can be broken down into manageable, iterative cycles, that allow teams to adapt and refine their strategies as they progress in the process. It's about being responsive rather than reactive so that teams can pivot quickly in response to feedback or changes in the environment.

There are four system modernization approaches that can be applied here:

  • Breaking the modernization process down into smaller pieces for frequent reassessment.
  • Encouraging close collaboration among diverse teams, all for more comprehensive and efficient problem-solving.
  • Establishing regular feedback mechanisms from users and stakeholders to align development with user needs and business goals.
  • Adopting a flexible planning approach that accommodates changes at any stage of the development process.

Take an incremental modernization approach

When it comes to modernizing legacy applications, an incremental approach often proves more practical than a complete overhaul. The appeal of this strategy lies in the fact that transforming everything overnight can be both risky and disruptive, not to mention often being simply impossible. Taking an incremental approach to modernization instead minimizes disruptions and provides a steady delivery of business value. If a company does not want to start from scratch, augmenting and refactoring its current operations may be a better option.

That means focusing on enhancing and improving the existing application by methodically refactoring its codebase. This modernization method is designed to optimize performance while maintaining integrity and familiarity with existing processes and systems. Following this method can reduce risk and complexity while allowing for integration of new or refreshed functionalities, without requiring a complete system overhaul. Needless to say – it’s usually more affordable than rewriting the code, which can introduce new bugs, or switching to another system.

The incremental modernization process is rather straightforward. First, determine which critical application areas need improvement or are more susceptible to causing problems. Then, plan and implement changes in manageable increments for a smoother transition. Introduce new functionalities or technologies gradually in order to meet the evolving needs of the business. To ensure the functionality and stability of an application, rigorous testing is necessary, or at least advised.

Any refactoring or modernization effort shouldn’t be done in isolation, but be closely aligned with business objectives to support business growth.

Leverage automated testing

The updates or changes made during the modernization process must not compromise existing functionalities. They should rather support continuous integration and deployment processes.

Choose a testing framework that aligns with your technology stack and supports various types of testing (unit, integration, system). Then, integrate testing into the CI/CD pipeline – running automated tests with every code commit are part of the continuous integration and deployment pipeline.

Regularly update and expand your test cases to cover new features and scenarios, to guarantee thorough application coverage. Analyze the test results to identify and address issues promptly, and continuously refine your testing processes according to feedback and based on data.

Focus on software maintainability and scalability

Architect the application with scalability in mind, using patterns and technologies that allow it to handle increased loads and growth seamlessly. The first element your business can apply that to is the code. Moreover, regularly refactor the code to improve readability and reduce complexity not only now, but also for future maintenance or expansions.

Document each step

Proper documentation of each change and update made during the modernization process will come in handy more often than you think it could. This documentation should not only record what changes were made, but also why they were made and how they impact the overall system.

Through mapping the application's evolution, a clear historical context is provided that gives insights into future modifications and troubleshooting.

Effective documentation usually includes the following main elements, which can be adjusted and expanded upon:

  1. updated technical documentation
  2. change logs
  3. decision records

Invest in knowledge transfer

Documentation is important, but it’s only documentation, and it cannot replace investing in the team's knowledge and skills.

To get started, you can implement all or some of the ideas below:

  • Run regular training sessions to keep the team updated on the latest technologies and best practices relevant to legacy code modernization or maintenance.
  • Organize knowledge-sharing sessions (“lessons learned”) among team members through workshops, seminars, and regular team meetings.
  • Consider implementing mentorship programs during which more experienced team members guide and support others.
  • Provide access to learning resources such as online courses or conferences.

This dual strategy (documentation and training) not only simplifies the modernization process, but also equips the team with tools for the future.

Which strategy and approach is best for your legacy application modernization?

Deciding which strategy to pick for modernizing your legacy applications really boils down to your specific needs and the current state of your legacy infrastructure. It's like choosing the right tool for a job you have to understand the problem first. Think about what your business goals are, the tech challenges you're facing, and how flexible you need your systems to be in the future. Are your apps just a bit behind the times, or are they practically ancient?

Sometimes, a simple update and a shift in your architecture might do the trick. Other times, you might need to dive deeper with more comprehensive approaches like Agile practices or incremental modernization.

In other words, you need to match the solution to your unique puzzle. Take a close look at where you stand now and where you want to be – the right strategy should help you move forward.

Make your IT legacy systems great again with the right software modernization plan

In application modernization, it's clear that the key to avoiding future legacy problems lies in an actionable plan and its ongoing implementation. These are not just one-time tasks but continuous commitments. Integrating them early in the workflow ensures the application remains reliable, adaptable, and aligned with technological advancements.

Our proactive software application modernization strategies reduce future legacy issues allowing applications to respond more quickly to ever-changing business requirements. If you are looking for a reliable partner for software modernization or are looking for help or advice in this regard - feel free to contact Polcode at any time. Reach out and let us how we can help you.

On-demand webinar: Moving Forward From Legacy Systems

We’ll walk you through how to think about an upgrade, refactor, or migration project to your codebase. By the end of this webinar, you’ll have a step-by-step plan to move away from the legacy system.

moving forward from legacy systems - webinar

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