Application Modernization: The Basics and 7 Tips for Success

What Is Application Modernization?

Application modernization involves updating legacy applications to a scalable, cloud native application environment using a modern technology stack. This ensures that applications continue to meet expectations as user needs and business requirements evolve.

Key business drivers for application modernization include:

In this article:

Why Application Modernization Is a Business Imperative

Up-to-date infrastructure is essential for a digital transformation – old infrastructure can hinder the development team’s ability to produce quickly and flexibly, slowing down the time to market. For an organization to stay competitive, it must use agile applications to leverage new automation and data processing solutions. In some cases, organizations commit to updating their infrastructure regularly – in other cases, organizations might overhaul their entire infrastructure. 

An organization that modernizes its applications can enjoy several benefits, including faster development pipelines, reduced costs, higher productivity, robust support, and new functionality. The most important benefit is to provide a good user experience, which is harder to do with aging infrastructure. 

Another significant benefit of application modernization is the reduced expenses of cloud or hybrid hosting strategies. This approach reduces hardware and maintenance costs, allowing organizations to leverage new services provided by a third-party vendor. For example, some service providers offer automation and AI-based capabilities that would be expensive and difficult to implement in-house.

Modernizing applications can also increase development agility and speed, allowing organizations to maintain a competitive advantage. Demanding customers often require ongoing rollouts of new features and upgrades. New technologies can also support flexible working models, such as remote work, contributing to staff productivity. 

Application Modernization Challenges 

The complexity and expense of application modernization can challenge some organizations. An inexperienced administration might not know how to conduct strategic assessments, replace legacy applications, or make appropriate modernization decisions. Navigating the modernization process is often a challenge, but the right solution can help guide the digital transformation. 

For example, there is a major global IT skill shortage, meaning that most organizations lack sufficient in-house expertise to plan and implement their digital transformation. A third-party application modernization service allows organizations to outsource skills. Another major challenge is access to the right tools. Modernization often involves complex re-platforming or refactoring processes that require special technologies. 

However, it is important to pursue modernization to prevent the biggest issue with aging applications – lack of support. Technology providers often stop supporting older applications. If an organization leaves it too long to replace these applications, it can be harder to navigate the modernization process without the appropriate support.

Key Patterns of App Modernization

Here are some common patterns organizations use when modernizing applications:

  • Microservices architecture—the most common pattern for application modernization is to refactor monolithic applications into smaller, loosely coupled collections of microservices.
  • Refactoring—taking a legacy application and rebuilding it to make it compatible with modern cloud environments. This typically involves restructuring and rewriting large parts of the existing codebase. This approach is common when converting a monolithic application to microservices. 
  • Lift and shift—taking a legacy application and migrating it to new infrastructure such as the public cloud. This model moves the application with little or no changes to the underlying code and architecture. This is a low-cost, low-complexity approach, but also means the application cannot fully benefit from the capabilities of the new environment.
  • Replatforming—this is a compromise between refactoring and lift and shift. It does not require major code or architectural changes, but does require certain updates, such as switching out the database, that can help the legacy applications run on a modern platform.

Related content: Read our guide to microservices architecture

Application Modernization Technologies

Here are some of the key technologies that facilitate application modernization.

Private, Hybrid, and Multi Cloud

The public cloud is an important part of a modernization strategy, but it is not the only option. Private cloud, hybrid cloud, and multi-cloud strategies can help organizations achieve their requirements in terms of security, latency, and desired application architecture. 

Hybrid cloud architectures are especially important to preserving the integration between modernized applications and remaining legacy systems. A multi-cloud approach, in which each workload runs in the cloud environment most suitable to its requirements (whether public or private) can alleviate many of the architectural and policy challenges of application modernization.

Serverless Functions

Serverless computing is an infrastructure model in which a cloud provider offers on-demand, fully managed computing resources. The customer only needs to provide a piece of code, known as a serverless function, and the cloud provider runs it on their servers in a transparent manner, taking care of scalability and all infrastructure concerns.

Behind the scenes, serverless computing relies on the cloud and physical servers to run serverless functions. However, it abstracts servers, operating systems, and other infrastructure from application developers. 

The main benefit of the serverless model is that complex tasks like deployment and autoscaling are handled fully automatically, freeing developers to focus on application development. Serverless computing can also save costs because customers pay only for the actual resources used by their serverless functions. 

Containers and Kubernetes

Containers and Kubernetes are key elements of application modernization strategies. Containerization allows applications to be packaged in a lightweight manner, allowing them to  run consistently on any computing system. Orchestration refers to the automation of operational tasks related to containers, such as deployment, scaling, and networking. This makes it possible to deploy and manage software components at scale—both legacy applications and microservices—and make them easily portable between environments.

Instrumentation for Observability and Security

Instrumentation allows applications to create and share metrics and logs. Observability is an important property of modernized applications—they should be built to enable visibility of their activity and performance, as well as easy identification and resolution of errors. 

Cloud native monitoring is different from traditional application monitoring, because monitoring systems must deal with a large number of distributed components and transient objects that are created and shut down on a regular basis. 

With this complexity, cloud native monitoring must identify traditional concerns like low disk space, high memory consumption, high CPU utilization, application errors, and unauthorized access. Achieving observability and visibility of cloud native systems is critical to ensure performance, cost effectiveness and security.

Related content: Read our guide to cloud native architecture

Application Modernization: 7 Tips for Success

1. Provide Visibility Across Legacy and Modernized Applications

Even if applications are modernized as microservices in the cloud, they still need to communicate with legacy systems in the enterprise. The problem is that there are many more services and environments to protect. This not only increases complexity, but also reduces visibility into the entire enterprise stack. 

Visibility across environments, especially between on-premises and cloud, are critical to success. You can achieve it by ensuring that modern applications fit into the organization’s existing data structures and integrate with legacy applications. Businesses need to capture operational data across the stack and act on it to ensure end-to-end performance and availability.

2. Modernize Organizational Processes, Not Just Applications

Application modernization is not just about technology, it is about people too. To succeed in application modernization, an organization must ensure the surrounding requirements are clear, and other stakeholders in the organization cooperate with the program.

Important constraints like compliance and quality requirements must be defined in advance and coordinated with the relevant teams. In addition, organizational processes like planning, requirements management, and resource allocation might need to evolve to support an application modernization program. 

3. Combine Modernization Strategies

Earlier in this post we presented several modernization patterns, including lift and shift, replatforming and refactoring. Organizations must be flexible in their choice of patterns, and also realize that some applications should not be modernized because the costs may exceed the benefits. By choosing the most appropriate modernization strategy for each application, an organization can achieve optimal ROI for its cloud native investment.

4. Prove the Returns of a Modernization Program

Whatever the initial business driver of application modernization, it is critical to gather metrics related to those objectives and demonstrate that the program is fulfilling them. 

For example, if a main driver for modernization was cost savings, it is important to track cloud costs in comparison to baseline legacy environment costs. If an important goal was improving application performance, it is critical to track performance of modernized applications compared to their legacy counterparts. 

5. Shift Security Left

Until recently, security testing was a step at the end of the software development lifecycle (SDLC), after application testing. It involved security testing using tools like static application security testing (SAST) and dynamic application security testing (DAST). This significantly delayed and complicated software delivery.

In a cloud native environment, waterfall-style security testing is no longer viable due to the high velocity of releases and deployments, making it a necessity to “shift security left”. The term “shift left” refers to the DevOps team’s efforts to secure applications early in the development lifecycle. It is part of an organizational model called DevSecOps. 

Shifting left means starting security testing from the onset of the development lifecycle, and running tests continuously at every step of the lifecycle. The goal of shifting security left is to design software that incorporates security best practices from day one, to identify and fix potential security issues and vulnerabilities early in the development process, which is easier, faster and less expensive.

6. Harden Infrastructure

Hardening is the process of protecting a system by identifying and reducing attack surfaces. As a system performs more functions, it presents more attack surfaces and vulnerabilities to attackers. Removing unneeded software, redundant user accounts or privileges, and non-essential services are all activities that can reduce the attack surface.

When securing your SDLC, application hardening should be built into the process. Every layer of the environment should be hardened—from the tools used in the CI/CD pipeline, to hosts running cloud native systems (such as Kubernetes nodes), to elements of cloud native applications such as serverless functions and container images.

7. Protect Workloads

A cloud workload is a function or task placed on a cloud instance that can contain files, containers, functions, or other elements. Cloud workload protection is the practice of identifying the security requirements of different workloads and protecting them from a variety of threats. Workloads can run across multiple physical hosts or even multiple clouds, making security more critical and complex.

Workload protection in cloud native environments is not feasible without automated tools, because the dynamic nature of these environments makes it very difficult to check and confirm security best practices for all workloads. Cloud workload protection platforms (CWPP) can automatically detect workloads, identify security weaknesses and assist the organization in remediating them.

Cloud Native Security with Aqua

Aqua Cloud Native Application Protection Platform (CNAPP) is the most comprehensive and deeply integrated enterprise platform for cloud native security. By delivering holistic end-to-end security in a single unified solution, Aqua secures the build process, the underlying infrastructure, and running workloads, whether they are deployed as VMs, containers, or serverless functions. Cloud native applications are protected up and down the stack, all the way from development to production, and across multi-cloud and hybrid environments.

The Cloud Native Experts
"The Cloud Native Experts" at Aqua Security specialize in cloud technology and cybersecurity. They focus on advancing cloud-native applications, offering insights into containers, Kubernetes, and cloud infrastructure. Their work revolves around enhancing security in cloud environments and developing solutions to new challenges.