Legacy Application Modernization

With legacy applications becoming outdated and burdensome to maintain, a lot of businesses transform their business applications to become more agile, mobile, productive and efficient. With majority of corporations running on legacy applications, the legacy application modernization process can prove to be a complex effort.

How should the enterprise approach the new demand for mobility, speed and customer/employee experience with already constrained resources and complex legacy application stack architectures?
How to quickly react and support the delivery of IT services to a highly mobile workforce without the legacy stack becoming a threat or impediment to your business  growth and development?
How to strike a balance between productivity ROI and the predictable cost associated with running your legacy architecture?

Application Modernization Infographics

Application modernization infographic

Tricension presents a complete guide to your legacy application modernization journey. Find the right approach to application modernization by addressing the precise issues behind your decision to modernize your applications in the first place:

Plan, perform a proof of concept, execute, learn repeat / iterative approach ?

Invasive or non-invasive approach?

Outsourced, blended or in-hours resources for the application modernization project?

Simple migration to commoditized cloud applications or integrating best of breed applications or a complete custom application modernization project? Which approach is best for your situation?

What Does Legacy Application Modernization Mean?

The centralized and overarching IT models along with fragile legacy applications stacks can no longer support the pace at which digital business initiatives take place. The IT needs to evolve to support and ingest the ‘new-normal’ technological innovation pace. Competitive pressures and growing functional requirements can no longer be supported by the layered stack of complex legacy systems that companies add over time.

With today’s competitive pace, mobility and agility is key. Recall the first round technology implementation of technology in the company?  In time, what once was large productivity gains become impediments to business growth. These legacy stacks create operational inefficiency, and stand in the way of a new era of user experience and big data-oriented technologies.

Companies that cannot rely on the overextended complex legacy applications are looking for ways to move forward without disrupting the long-established business processes.

Our Legacy Application Modernization methods and governance processes help organizations move from the “as is legacy systems status” to the “future state” of agility, data driven and optimized business systems.

Legacy application modernization is the process of aligning legacy software application stacks with the current business needs and functionality requirements. There are many reasons for the organization to embark on an Application Modernization journey, however the two most common driving factors are cost reduction and productivity enhancement.

Legacy Application Modernization vs. Cloud Migration

It is important not to confuse the application modernization with application migration.

Application modernization

involves modernizing, refactoring or re-architecting the legacy business systems to better respond to the current business needs, market changes and data driven decision making.

Application migration

involves moving business applications to a completely different computing platform to improve reliability, scalability, security and cost of computing economic model.

The main goal of migration is to replicate the current functionality in a more agile computing environment, while the goal of modernization is to improve or replace the business functionality of the core systems.

In the case of modernization the legacy stack does not necessarily need to be moved, however ‘migration’  (e.g. ‘cloud data migration’) can be PART OF modernization project if it is necessary for achieving the desired systems abilities such as agility and scalability.

Benefits of Application Modernization

Before deciding on the best way to approach the application modernization feat, the  organization needs to have a clear vision of where it is going and the organizational value of the future state.  

Therefore the benefits your organization would gain from the modernization project will completely depend on your organizational vision and goals. By a large margin, most legacy application modernization projects are launched for one of the following reasons: productivity gains and to support business growth.

Productivity Gains

With a lot of organizations still running its processes on the old technologies which are monolithic in nature, legacy application modernization has become the strategy du jour for achieving systematic efficiency with mobility, agility, and data driven decision making.


Organizations need to be able to quickly respond to technological and digital innovations in today’s dynamic and competitive environment. Legacy applications are complex, fragile, and most importantly, monolithic, requiring high resources consumption, technology budget and putting a lot of strain on the ability to keep up with the demand. Application modernization helps to reduce dependencies, automate processes and deliver new technologies driving agility and innovation. Thus the technology will become the enabler of business transformation.


Application modernization can become a catalyst for migrating your modernized applications to the cloud environment, which delivers broadly recognized public cloud benefits of speed to market, agility, scalability.

Intellectual property Protection

Modernization is aimed at replacing legacy applications while preserving important intellectual business property such as methods and processes.


There are critical compliance and security standards that organizations cannot ignore. Compliance with these security standards helps reduce the risks to its customers, employees and partners.

Business Growth

Organizations report spending a large share of their IT budgets, time and resources on maintaining complex legacy systems, running at-capacity, with little room left for innovation. Properly delivered legacy application modernization offers faster software delivery which is crucial for staying ahead of the competition and maintaining a sustainable business growth.

Agility that goes hand-in-hand with application modernization allows organizations to deliver new products and services efficiently and at a faster pace, promoting business growth and development.

Application modernization helps to free up resources for more innovation and improvements. Organizations will be able to better align its business and IT goals by reducing the time required for maintenance and freeing up the resources for innovation and business growth instead.

Application modernization delivers the right environment that facilitates the growth and development in today’s increasing pace of technological change, instead of stifling it. Modernization allows businesses to leverage all the most critical changes that drive IT transformation: cloud, big data, compliance, mobility and virtualization.

Overall, application modernization helps organization to adapt to the new technological realities without having to completely replace the systems that are crucial to the business processes. So while it becomes quite evident why organizations around the globe are embarking on application modernization journey, the best way for any organization to get to the final destination will depend on the proper planning and execution to make it a low-risk and cost-effective endeavor.

Legacy Application Modernization Path

Application modernization is aimed at aligning business applications to meet the current business vision and goals, determine solution patterns to achieve this, leverage microservices, SOA, public cloud, containers, DevOps, AI and much more.

When you approach the legacy application modernization, ultimately you are looking to extend and maximize the value of your “secret sauce”, the important intellectual business property such as methods and processes. A successful application modernization roadmap is geared towards choosing the right solutions approach and technology stack without disrupting the current business processes.

Assess application portfolio

Evaluate your current application portfolio: current legacy environment, application usage, interdependencies, data types and establish how it aligns with the current business objectives.

Assess options and choose the right strategy

What are the potential solution paths and what is needed to achieve the desired business objectives? Evaluate various options and choose the most optimal combination of solutions, tools, techniques and efforts to achieve the required business outcomes. Prioritize your business needs and align the needs with modernization path, available resources and timeline. Outline detailed milestones and map all operational areas.

Assess effort, cost and timeline

Identify various modernization options driven by your application assessment and business objectives. Are there sufficient resources to commit to the project? What are the budgetary constraints and timeframe requirements?

Mainframe applications (which today often become liabilities, inhibiting competitive reaction to new market changes and liabilities) should not impede organizations from reaching its digital goals. The best and most suitable legacy application modernization roadmap will address these obstacles, by deploying a combination of tools, platforms and strategies.

Legacy Application Modernization Strategies & Approach

After carefully evaluating the current legacy environment, it is important to select the right modernization approach that will be the most beneficial for both the business objectives and the limitations. Depending on your goals, there are 6 different most common approaches to modernization:


Involves completely rewriting the application. This approach can possibly deliver the best outcome, however is one of the highest risk endeavors especially for larger projects, due to very high costs.


Involves re-deploying and running the application on a different platform or cloud without major functionality, code and features changes.


Involves rebuilding the legacy applications in a new environment by altering code to support the new functionality, while eliminating the factors that stifle your agility yet preserve the business critical functionality.


Involves the rip-and-replace approach, which usually entails replacing with a different component or package with similar functionality.


Involves migrating the application to a new platform or optimizing to improve functionality with minimal changes to the code.


Involves optimization of the code without changing its external functionalities through refactoring its structure and features.

Refactoring a Monolith: SOA, Microservices and Containerization for Legacy Application Modernization

Monolithic applications stifle the organization’s innovation, modification and evolution. Today, application modernization process looks towards new technologies that deliver Continuous Delivery, Agility and DevOps. Componentized approach to development and deployment is what ties agile development, continuous delivery and DevOps together. Unlike the traditional non-containerized services SOA sought to streamline, these are now deployed as focused modular functionality snippets using containers and microservices.

With microservices, developers extract modules and functions from the legacy application that run in a container. In other words, refactoring a monolith using containers and microservices allows organizations to keep the business logic or certain features that they cannot just yet replace, while moving the functionality to new upgraded components.

What are the Containers and What Role Do They Play in Legacy Application Modernization?

Containers ensure that the software always runs smoothly and securely regardless of the environment it runs in. In other words, container is a software-defined environment, that has everything it needs to operate: code, tools, libraries. Because the software wraps up and abstracts the code from the system, it runs the same in any environment. Such ‘fragmentation’ offers easy portability, improved distribution of computing resources, scalability and less dependencies in infrastructure.

What are the Microservices?

Microservices are the functional elements of small independent processes that are tied together with language-agnostic APIs. The microservices are an architectural pattern, which break down the legacy application into functional elements and transform them into sets of services which can be leveraged by various applications.

As opposed to the SOA-based large-scale infrastructure, microservices which are tied together with APIs, form building blocks which can be extended to other parts of business and redeployed as many times as needed, forming a network of highly agile functionality.

The main goal of microservice architecture is delivering applications that consist of autonomous self-contained units which do not have any dependencies on other microservices. As opposed to traditional libraries or code modules, microservice units act as one unit of execution, and contain everything to run completely independently, from frameworks to operating systems.

Microservices and Containers: Missing Links of SOA Principles

IT debt in enterprises has become so widespread, that legacy application modernization has to become a part of an ongoing activity for most organizations.

To address the increasing need for continuous modernization and agility, enterprises turn to containers and microservices for cost-effective and scalable solutions. Containers allow to modernize legacy application without lots of reprogramming when transferring from one environment to another. However, containers don’t allow to break down a monolith into smaller elements effectively. At the same time it is not efficient to add new functionality by adding more code.

Microservices allow to add new functionality in the form of stand-alone features that provide functionality to the rest of the monolith or finding a service which can be converted into a microservice and delivered via the API. That way, organizations will be able to separate various re-usable functions and application modules that will run in a container.

Container technology such as Docker containers allows portability of code across multiple environments enabling applications to run inside the container. Moreover, it allows you to manage containerized workloads with tools  like Kubernetes.

Microservices along with containers will help organizations to streamline the modernization processes by eliminating interdependencies and making the applications more agile and elastic:

Self-contained microservices allow to monitor, fix and update a service without the impact to other services

Organizations will be able to choose from a wide range of operating systems, frameworks, databases, runtimes, databases and tools

Organizations will be able to invest into a set of core composable and reusable microservices and use these to build a wide range of applications

Microservices allow to consume legacy application functionalities and services that will also be accessible by other applications, without having to build these services from the ground up

Streamlined development planning allows organization to allocate resources faster promoting business growth

Scalability allows businesses to increase or decrease software in line with the current business requirements

To operate your containers in the cloud it is recommended to apply the principles of CloudOps to take advantage of its architecture: containers have to be managed not just as distributed components that function together as an application, but also as unique components that can be scaled on its own. CloudOps delivers a  unique way to create auto-scaling and make use of resources as the requirements change.

Containers and microservices open up a world of possibilities for legacy application modernization, to make them scalable, elastic and service-oriented. However, before deciding on a certain approach to modernize, thorough evaluation and consideration is needed: not all application are candidates for this approach. For instance, it is often cheaper to rebuild rather than refactor very old or poorly designed applications. Although microservices and containers do deliver more distribution and agility, the modernization should also result in cost-efficiency and productivity.

Tricension Software Development & Tech Advisory