Software without developer’s support. Impossibility to install app updates. Performance bottlenecks when the number of users grows. Maintenance costs skyrocket. Headaches every time a new feature has to be added. No seamless testing of innovative technology.

Legacy systems experts can identify with the previous statements. These are common and recurring problems. Yet, the main obstacle is a different one: legacy systems often hinder business growth, rapid adaptation to new market demands, or the creation of innovative user experiences.

With this in mind, a PE investing in a company to increase its market value must understand that one of the priorities is to modernize systems. This means transforming the old monolithic and generally very “heavy” into inflexible structures to open models based on new languages and supported by an accessible infrastructure and platform service.

From the particular to the general

There are different modernization strategies. Choosing a strategy will depend on the outcome sought, the resources available, the possibilities offered by the source code of the legacy application (Is it accessible? Can we control it? Can we modify it?), the level of dependency of this software on other solutions (and how each change would impact them) and how critical downtime is.

The first and most straightforward option is usually to put the decision off and do nothing specific. The reality is that taking this path is only valid when the business benefits to be gained from modernization are not justified in relation to the cost of the project or the risks it may generate. In some cases, waiting is unavoidable: for example, when the application depends on others not yet been modernized.

The second options relocation. The application is simply moved to a new infrastructure, generally by means of containers or to the public cloud. This is a simple and inexpensive option whose benefits are equally limited. It can only reduce maintenance costs, enable greater scalability, and improve hardware utilization. As an alternative, one may think of introducing minor code changes to help utilize cloud resources, such as the database, authentication, or full-text search services.

Towards microservices

Another popular option is to expose the solution as an API (application programming interface): interfaces that allow system elements to communicate and be available to others for use. This option also requires minor changes but it adds a critical benefit that eliminates one of the pain points inherent to the legacy world. It allows you to modernize the front end. It is no longer necessary to use the legacy system interface to access the front-end. Instead, an innovative web or mobile interface can be created. This approach can be combined with the previous options.

Often, applications were not built for the scale they encountered in this hyper-digitized era. In this case, refactoring (architecture remodeling) comes to the rescue. The most common method (there are different options) is to split monolithic applications into microservices, keeping functionality intact.

Deep modernization

The most drastic strategy is to replace the old system with a new one or rewrite the code thoroughly. This is the inevitable step when the functionality no longer fits the business needs, the resources or skills are unavailable to modify the code, or a better product that meets the organization’s requirements appears on the market.

This is the most complex and risky path in terms of modernization and has different approaches. From the big bang, where the new application is built, thoroughly tested, and installed, replacing the old one in one go – having previously prayed, of course, and having a reversion plan B in case things do not go well – to a previous division of the monolithic application into microservices and partial implementations, through parallel execution, which consists of keeping the data synchronized between both systems and if something goes wrong in the new one, appealing to the old one to fix it.

The roads are numerous, with different costs, risks, and benefits. Each organization must assess and choose the one that best suits the moment’s needs. The goal is always to count on technological support to increase the company’s value.