They have always been there: recording transactions, supporting the core of the business, gaining maturity and stability over the years. The fear of modernizing legacy systems is latent in any company embarking on a path of digital transformation. Apart from the aforementioned benefits of robustness, guarantee of operation and accumulated knowledge of the business, there are also some disadvantages such as the lack of agility to adapt to changing times, the risk of technological obsolescence, the inability to integrate with innovative tools or high maintenance costs.

The modernization of these monolithic schemes, which perhaps played an essential role in the development and growth of the organization in the past, is essential to keep being competitive and flexible for the future.

The dilemma is proposed: they cannot be ruled out, because these systems house an enormous amount of data collected throughout the history of the company, but neither can they be kept as the center of digital operations, considering that the world of business is asking for something else.

Evolution or revolution

What is “modernizing” a legacy system? First of all, it means solving the technological limitations that it may have to gain efficiencies, continue to satisfy the expectations of users and customers, reduce maintenance costs and, fundamentally, follow the business guidelines. All this, guaranteeing that the data it contains is not lost and it can be used in the new scheme.

The scope of modernization covers a huge spectrum: from small modifications or the use of some emulation or virtualization tools so that the old system can continue to function in the framework of more modern technologies to a total redesign. This last case is what is called the “revolutionary approach”: the complete transformation can originate in a drastic change in the company (a focus on new markets, a merger or acquisition) and also in cases where the legacy system has some type of risk.

The most common case, however, is one that seeks a gradual evolution, with the aim of minimizing downtime and commercial disruption and to distribute project costs over a longer term.

The 7 «Rs»

According to the consulting firm Gartner, the models with which a modernization of legacy systems is faced are:

– Encapsulation: leverages and extends the characteristics of the legacy application by encapsulating its data and functions and makes them available as a service through an API or some other exchange model.

– Rehousing (or rehosting): It moves the elements of the legacy system to a new infrastructure (physical or cloud). In general, it applies when the application is on a mainframe and needs to move to a more modern base.

– Platform restructuring: It is migrated to a new runtime platform, with minimal code changes.

– Redesign or refactoring: Optimization of some aspects of the legacy system to achieve better performance. They are changes in the backend, but not in the external behavior (frontend).

– Re-architecturing: The code is altered to adapt to a new application architecture and exploit new and better capabilities.

– Redevelopment or reconstruction: Completely redesigned the system in order to take it to a native cloud environment.

– Replacement: It consists of discarding the existing system and implementing a new one. The availability of complete solutions in the cloud makes this an increasingly well-traveled path, particularly when it comes to the migration of non-critical systems.

Each approach has its pros and cons. In general, the first ones require less effort, but also produce less impact on the organization. The most important thing: choose the strategy that brings the greatest value to the company and at the same time, it allows its penetration into the future of business in the best possible way.