Full Guide of Legacy Software Assessment
Outdated systems evoke intriguing conversations among tech geeks because there is no one standard way of testing a legacy system to assess its functionality. While these systems can work effectively for years, it reaches a point where the costs of maintaining and optimizing legacy software become unreasonably high. This is not to mention the low-performance issues due to incompatibility with new technology.
But why should you test legacy software, and how are legacy systems assessed in the first place? This article highlights the reasons for assessing a legacy system, the steps to follow, and the challenges you’ll likely experience. Read through to stay updated.
Assessment of Legacy Software: What Is It?
The assessment of legacy software is a high-level process that involves examining and evaluating the components of an old system. Old software, in this case, is a system architecture that has served your business for five years or more without servicing.
Typically, this assessment helps you point out the system’s strengths and weaknesses to determine whether it can meet the prevailing needs. If not, exploring legacy modernization solutions should be the next step.
Legacy system assessment is a critical step for any IT-driven industry. However, the following sectors may benefit more and have a competitive edge after evaluating legacy software to modernize it:
- Healthcare: conducting a thorough evaluation of outdated systems can help healthcare organizations optimize their software for HIPAA regulatory compliance.
- Financial services: all financial institutions that leverage a legacy solution can assess it to identify and mitigate compliance or security loopholes.
- Manufacturing: manufacturers can evaluate their old software architectures to identify cost-saving opportunities and integrate new technologies, such as IoT.
- Government: governments can audit their old operating systems to implement digital transformation and improve service delivery in growing populations.
Generally, organizations implement legacy software assessment when planning to upgrade the existing solution as part of a bigger digital transformation agenda or to meet current business needs. Also, evaluating older software can help identify integration challenges for proactive remediation before implementing an upgrade.
Reasons Why You Need to Assess Legacy Software
Although legacy systems are technically out of date, some organizations still use them to complement various business functions. But even if your old operating system works, you might want to evaluate it due to the following reasons:
Security risks
Older tech solutions aren’t built to withstand advanced cybersecurity exploitations, which can jeopardize the security of your entire IT infrastructure. In this case, legacy software evaluation will help you identify security vulnerabilities and suggest remediation measures to seal the loopholes.
Performance challenges
You can assess legacy software to identify the performance challenges it might have developed over time, such as memory leaks, sudden outages, or slower responses. This helps you pinpoint the root cause of slowed performance and ways of solving the issue.
Old technology limitations
Conducting a thorough assessment of your system is the first step to overcoming the tech limitations of legacy software. These limitations include a limited integration functionality, which can hinder key modernization steps, such as data migration.
Regulatory and compliance requirements
Another reason to evaluate your old software is to find regulatory compliance gaps that may put your business at risk of huge losses in fines and a tainted reputation. Technically, assessing a legacy software helps you establish whether it meets the current regulatory standards.
The cost reduction factor
Testing a legacy system to assess its functionality can help you identify cost savings opportunities, such as moving to a cloud based platform. This is cost-effective in the long haul because you won’t strain meeting expensive legacy system maintenance costs like acquiring specialized software.
8 Steps to Assessing a Legacy Software
Knowing how to assess legacy software can be an uphill endeavor at first, thanks to the complex and challenging process. Follow these steps to get started:
1) Define the goal and scope
This step entails understanding why your organization built the software in the first place and the primary function that it serves. Having these details will help you understand how to identify a legacy system component that’s critical in driving key business functions.
2) Code quality evaluation
Your legacy code was written in programming languages that don’t match current standards, making it imperative to evaluate its structure and complexity. Assessing the code helps you understand its maintenance needs and scalability or performance capabilities.
3) Single out dependencies
As an outdated system, legacy software often includes retired hardware or software components in its architecture. In this step, single out these components, or dependencies, to examine whether they are still functional.
4) Establish security risks
The old technology platform might pose higher cybersecurity risks since it doesn’t feature an automatic update functionality to patch vulnerabilities. With that in mind, examine it carefully to identify security loopholes that are susceptible to easy exploitation.
5) Examine documentation
Typically, legacy software is associated with poor documentation, making it important to assess whether the existing documentation is adequate or requires an update.


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6) User feedback analytics
Conduct a poll or questionnaire survey to gather feedback on the system’s level of user experience. Doing this helps you to collect insightful feedback to help optimize the software’s usability or functionality.
7) Calculate the maintenance costs
Add the total budget for maintaining the old technology platform. While doing so, remember to factor in debugging expenses and the costs of upgrading dependencies. Also, consider any other expenses that might be incurred to optimize it for compatibility with modern technology.


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8) Strategize an action plan
Lastly, develop a solid plan based on the findings of the legacy system assessment, and outline the next steps to follow to fix the identified issues. Again, it will help if you take a long-lasting approach that won’t sink your organization into technical debt, even if it means re-platforming, migrating, or building a new platform from scratch.
Challenges of the Legacy System Assessment
There are several common challenges that organizations face when testing legacy code, including:
Documentation can be scarce and/or outdated
One of the first challenges you’ll face when assessing a legacy system is a lack of documentation. Over the years, documentation can simply disappear. Even when you find the documentation, it can be outdated and misleading, as it may not reflect the current state of the software.
Large monolithic applications are difficult to comprehend
Another challenge with legacy software is that it can be very difficult to understand. Large, monolithic applications can be complex and confusing. And when you can identify and isolate issues, it may be difficult to implement changes without introducing new problems.


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Requires a lot of time and effort
Testing a legacy system can be a time-consuming and labor-intensive process. It can take weeks or even months to fully understand an application. And, once you have a clear understanding of the application, you still have to identify any issues and make recommendations.
Automated testing may not be possible
Automated testing is a vital part of the software development process. It helps identify errors and potential problems early in the development cycle. However, automated testing may not be possible when evaluating legacy software. This means it is difficult to perform regression testing and to ensure that changes do not introduce new issues.
Disruption to business-critical processes
When you test legacy software, changes may have to be made to the software or how it is used, which can disrupt business-critical processes. This can cause downtime or business disruptions.
To avoid this, a phased approach is best. Adopt agile methodology when doing your assessments and manage the process in small incremental phases or chunks.
Our Expertise in Legacy Software Audit and Assessment
ModLogix is a full-service modernization company helping businesses across all industries transform their tech heritage into a limitless potential for future success. We offer all the latest software development methodologies, including agile and low code, to help you optimize the process as much as possible and cut unnecessary costs.
Our legacy system modernization case study demonstrates our capabilities in evaluating platforms for functional upgrades. For instance, we helped a reputable IT and healthcare service provider in the healthcare industry upgrade from AngularJS to Angular 11. Although the project is still ongoing, the client now enjoys an optimized code that is six times shorter, a higher ROI due to improved performance, and long-term technical support. Let us know about your system integration pain points, and we shall deploy a business-ready development team to iron out the issues. Contact us today for a free consultation.
Final Thoughts
Understanding how to test legacy software can be a complex process, not to mention its expensive overhead costs. However, the long-term benefits of understanding and addressing your system’s weaknesses will eventually pay off in positive ROI.