Legacy System
Legacy System is an information system, software or technological solution created earlier that is still used in an organisation, even though its architecture, functionality or support options no longer meet today’s needs. Such systems often run for many years and are closely tied to day-to-day processes, so it is not easy to give them up. Over time, however, they become an obstacle to an organisation’s efficiency, security and service quality.
In the public sector, legacy systems are especially common, because municipalities, schools, museums, libraries and other organisations often work with limited budgets, and technology upgrades are postponed until the system still “works”. In practice, this may be an old content management system, an unsupported document management platform, an outdated registration form or a database created specifically many years ago. Although such solutions at first glance allow work to continue, they often cause more and more technical and organisational problems.
How do you recognise a legacy system?
A legacy system is not necessarily very old based only on its creation date. The main sign is that it becomes difficult to maintain, difficult to integrate with other systems and no longer meets modern security, accessibility or user experience requirements. Such a system may work stably, but every change in it becomes expensive, slow or risky.
- Unsupported technology. A system may have been built using a programming language, platform or server environment that is no longer supported by the vendor or community. This means that security updates are no longer released, and finding specialists who can make changes becomes increasingly difficult.
- Limited integration options. Legacy systems often do not have modern APIs or standardised data exchange solutions. This makes it difficult to connect them with e-services, document management systems, registration platforms or other public-sector tools.
- Outdated user interface. Older systems are often created without taking account of today’s usage habits, mobile devices or a clear information structure. As a result, it becomes harder for residents, staff or partners to use the services, and the likelihood of errors increases.
- Security and compliance gaps. If a system is not updated, vulnerabilities may remain that pose a threat to data security. For public bodies, this is especially important, because they often process personal data, so it is necessary to ensure compliance with GDPR requirements and proper access control.
Why do legacy systems become a problem?
At first glance, an old system may seem like an economical choice: if it still works, why replace it? However, in the long term, legacy solutions often cost more than a planned upgrade. Every small change requires more time, testing and additional security measures.
For municipalities, this may mean slower e-services for residents; for schools, inconvenient publication of information for parents and the community; for museums, limited opportunities to present digital content; and for libraries, registration or event-publicising systems that are harder to manage. When technology no longer meets today’s needs, not only staff efficiency suffers, but also public trust in digital services.
Accessibility and compliance
Digital solutions in the public sector must be accessible to all users, including people with disabilities. Legacy systems often do not meet modern accessibility requirements: they may lack sufficient contrast, keyboard navigation, a clear heading structure or compatibility with screen readers. This means that for some users, services become difficult or completely inaccessible.
The data protection aspect is no less important. If a system was created earlier, it may not have clearly defined data retention periods, activity logs, user-rights management or secure data transfer tools. Therefore, when modernising or replacing a legacy system, it is necessary to assess not only the technical condition, but also GDPR, cybersecurity and document management requirements.
How does the transition from a legacy system take place?
Moving from a legacy system to a new solution must be done responsibly and in stages. First, it is important to assess what functions the current system performs, what data is stored in it and which processes are essential for the organisation’s day-to-day work. Only then can a decision be made on whether it is worth modernising the system or more appropriate to replace it with a new one.
Data migration is one of the most sensitive stages. It is necessary to ensure that the transferred data are accurate, that historical information is not lost, and that users do not experience major disruptions. For public bodies, it is also important to manage the change transparently: inform staff, train users and plan the transition period.
When is it worth making changes?
If a system no longer allows security, accessibility, convenient administration or integrations with other solutions to be ensured, this is a clear signal that it is time for change. The same applies when an organisation becomes too dependent on one supplier or on a few hard-to-find specialists. The longer an upgrade is postponed, the greater the risk that the change will later have to be made more urgently and with greater difficulty.
Legacy System is not just a technical term – it is also an organisational challenge linked to service quality, data security, accessibility and long-term operational sustainability. Therefore, it is important for public bodies to regularly assess the digital solutions they use and plan their upgrades not when the system has already stopped working, but when it no longer meets modern requirements.