How to Choose Application Modernization Strategy

Topic: Guides

Author's photo

Before we dive into legacy application modernization strategies, we need to understand what a "legacy application" is and why we're talking about it.

Legacy application refers to an outdated or obsolete application that is still functional and in active use. This application can present challenges in terms of maintenance and support, as it may not be compatible with modern operating systems or hardware. However, it is important to recognize that a legacy application can have significant value as it contains important data and functionality that is not present in more modern applications.

There are various reasons why companies may continue to use legacy applications. Here are just some of them:

  • The cost of replacing a legacy application may be rather high.
  • A legacy application may be so well integrated with other systems that it may be difficult or impossible to replace.
  • Some companies may simply not want to change, even if there are good reasons to do so.

However, if legacy applications are not modernized for too long, they cause problems with maintenance, integration and user interaction. They can also hinder business goals and lead to costly and reputation-damaging data breaches. In addition, it will be extremely difficult for the business owner to find developers who are proficient in outdated programming languages to effectively maintain the existing system.

Legacy application modernization is the ultimate solution in this scenario. So, what exactly does it entail? It is the transformation of applications built with outdated technology into contemporary applications built with the latest technology. The process of modernizing such applications may entail the addition of innovative solutions to enhance the existing systems, replacing legacy applications, or even completely transitioning to a new approach.

Modernizing legacy applications is not an easy task and can take months or even years. That's why we've prepared a step-by-step guide to help you get started.

Evaluate Legacy System

First of all, business owners must assess their current legacy systems and understand why they need to modernize them. When evaluating and modernizing legacy systems, they should answer the following questions:

  • Does the application have an excessively high total cost of ownership?
  • Is the application demanding excessive supervision for management and implementation?
  • Does the application expose the business to new security risks?

If their answer is "yes" to any of these questions, it means it's time to think about an application modernization strategy.

  • Does the application align with current industry standards and best practices?
  • Is the application still meeting the functional requirements of the business?
  • Is the application scalable and able to handle future growth and increased demand?

If their answer is "no" to any of the questions above, they should also implement an application modernization strategy.

Choose Modernization Approach

Before embarking on a change, business owners need to know all of their options, so they can make the right choice. Here are 5 application modernization strategies to consider when building and modernizing IT roadmap:

  1. Rehost
  2. Refactor
  3. Rearchitect
  4. Rebuild
  5. Replace


The Rehost strategy, also referred to as the 'lift and shift' model, is an effective way to migrate workloads using cloud Infrastructure-as-a-Service (IaaS). With this approach, enterprises can effortlessly move applications to the cloud without making any changes to the core infrastructure. All data and application workflows are seamlessly transferred to cloud services. The beauty of the Rehost strategy lies in its simplicity and versatility, making it an ideal choice for enterprises of any background, even those without prior experience in cloud migration.

Even if this appears to be the simplest option, this approach does not fully exploit the advantages of a cloud-native environment. Simply transferring existing applications, especially complex legacy systems, to the cloud infrastructure does not enable the use of essential cloud-native features. These features include Platform-as-a-Service (PaaS), multi-cloud support, microservices architecture, agile methodologies, containerization, etc.


Refactoring is complex but the best choice for migration because it restructures workloads and fully embraces the cloud. Despite the effort and resources required, it enables applications to utilise advanced features such as serverless computing, autoscaling and load balancing.

Refactoring helps break down a monolithic application into microservices to achieve high availability and increased levels of automation, which are often difficult to realize when deployed in-house. While rebuilding applications to a service-oriented architecture can be costly during the migration phase, the operational costs of a well-planned resulting framework are significantly lower than operating a legacy framework.

Refactoring is a powerful technique that improves the efficiency of code. It involves restructuring code to eliminate technical debt that can contribute to various problems in legacy software. These problems may include outdated libraries, frameworks, code, or incomplete and inefficient features.


This modernization strategy involves transforming our legacy monolithic application into a cutting-edge microservices model. This entails breaking down our current application into a series of independent services that can be created, deployed, and managed with ease.

This 'divide and conquer' approach to architecture gives us more control and provides benefits such as business agility, faster time to market, lower costs and the ability to redefine the customer experience.


This app modernization strategy is similar to rearchitecture. However, as in the case of an old house, instead of remodeling it, it is sometimes more reasonable to rebuild it. This usually gives a much better result compared to remodeling.

When rebuilding, the application is transformed into a cloud native application, which leads to accelerated innovation, faster value release, and reduced operating costs. It is noteworthy that, thanks to technological advancements, modern languages, frameworks, and other advantages, the effort needed to initially build a legacy application may be substantially less than what is required to rebuild it today.


Replacement entails substituting the outdated application with a commercial off-the-shelf software (COTS) package or a Software-as-a-Service (SaaS) solution. This approach proves advantageous when the current application fails to satisfy the organization's requirements, and a promising alternative exists in the market. It can deliver rapid implementation, minimized maintenance expenses, and the opportunity to utilize novel features and functionalities.

Inventory Data and Map It to Business Processes

No matter which application modernization approach the business owners opt for, it is crucial to guarantee the accessibility and protection of their most vital data during the entire modernization process. Conducting a comprehensive inventory of the data they store and the business processes involved is essential to ensure uninterrupted operations while migrating or upgrading applications.

This is the perfect moment to explore options for data liquidation. Why hold on to data that is no longer necessary? By finding ways to free up data that needs to be migrated or moved, they will greatly reduce the time and complexity involved in the process of modernization.

Determine Budget

Financing technology modernization strategy is a distinct process compared to traditional IT budgeting, especially for organizations that heavily rely on monolithic or legacy applications. Traditional IT budgeting typically involves stable amounts with few unknowns and year-to-year fluctuations. However, modernization inherently includes a significant degree of uncertainty that must be taken into account when determining the budget.

Modernization is an ongoing process that completely transforms an organization's technological landscape, impacting the organization as a whole as well as its budget. Thus, it is important to calculate the return on investment (ROI) and total cost of ownership (TCO) in order to showcase the true value of the upgrade project to the organization.

Determine Timeline

Legacy application modernization requires time and careful planning. The duration of this process hinges on the complexity of the changes as well as the chosen IT modernization strategy. To ensure success, it is crucial to establish a detailed timeline and define clear metrics for measuring progress. By doing so, the business owners can maintain direction and stay on course.

Along with the timeline, they need to define the goals they want to achieve by each date. How will they know if their team is meeting the targets? What productivity gains do they expect to see? What factors will tell them that they are not meeting their goals? The answers to all of these questions should be spelled out in an application modernization roadmap, which is a carefully crafted document that outlines all the application modernization steps.

The application modernization roadmap should include clear key performance indicators (KPIs) by which the success of the modernization process can be judged. KPIs should address speed, uptime and downtime, security, and cost-effectiveness. They may also relate to customer satisfaction and other success indicators related to specific functions of customer-facing applications.

Create an Application Modernization Team

Creating a dedicated team to handle the application modernization process can ensure that the project runs smoothly and stays on schedule. When forming such a team, the skills, professionalism, and experience of each of its members should be taken into account. It is optimal if the team includes several IT specialists and department managers.

Both large organizations, where departments are often deeply isolated from each other, and smaller companies may need help with communication between departments. When it comes to application modernization, effective communication is essential as it affects the whole organization. If something is going wrong in the customer relationship management system, sales will be the first to know and can often suggest how the IT team can improve the situation.

On a Final Note

As a company with more than 20 years of experience, Cyfrania regularly offers application modernization services to its customers. We always identify technical issues within the app, rank their importance, and estimate the cost of repair. This covers:

  • Outdated data and databases
  • Technical causes of performance issues
  • Outdated integrations with external services
  • Obstacles to expanding functionality

If your application is facing one of these challenges, don't hesitate to contact us. We'll assess business challenges and priorities, explore options against budget, and help you choose the right application modernization strategy.

Related Posts