Modernize your legacy applications in the cloud

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  • Application modernization should be a significant aspect of any business-first cloud transformation with AWS.

  • Three common ways organizations are building cloud-native applications are through serverless computing, containerization and re-platforming.

  • Building and running cloud-native applications frequently contribute to overall improvements in scalability, reliability and cost efficiency.

If not now, when? That’s the question to ask about modernizing your legacy applications. Today there’s a pressing need as businesses rush to support a long-term, at least partially remote workforce — as well as rapidly changing customer needs brought about by the global health crisis. Companies are looking for new ways to add resilient, cost-effective software systems with few external dependencies, like on-premise work collaboration or hardware resources.

Application modernization is the process of creating new business value by reinventing the way that your applications are built, utilizing scalable applications in modern, dynamic cloud environments (known as cloud-native applications). You can also re-platform existing applications with programming adjustments so they run in the cloud with all their dependent components. Application modernization should be a significant aspect of any business-first cloud transformation. The ROI on such efforts can come quickly.

When modernizing and deploying with Amazon Web Services (AWS), for example, enterprises can reduce the payback period to as little as six months, cutting total cost of ownership by 64%. Building and running cloud-native applications frequently contribute to overall improvements in scalability, reliability and cost efficiency.

While there are many pathways to modernize legacy architecture, three common ways organizations are building cloud-native applications are serverless computing, containerization and re-platforming.

Each approach uses a different set of methodologies and is applicable to a distinct set of use cases. The first step is to determine the approach or approaches best suited for your business.

1. Serverless computing

Going serverless can help your organization shift more operational responsibilities to the cloud without relying on or thinking about your own on-premise servers. This can increase your business agility and supports experimentation with new products, services, technologies, features and business models. Serverless computing allows you to build and run applications and services by eliminating infrastructure management tasks such as server or cluster provisioning, patching, operating system maintenance and capacity provisioning.

There are any number of good use cases for serverless, such as building new applications, or modernizing pre-existing applications that have become too fragile in their current state. It can also be used effectively when transitioning from legacy data warehousing to an AWS cloud-native data lake. 

Serverless computing is a more viable solution when your organization needs to execute resource-intensive code such as an image-processing pipeline. It’s useful on an ad hoc basis when something unexpected comes up. And serverless excels when traffic patterns rise significantly or unexpectedly, automatically detecting load changes, adjusting instantly and scaling without effort to meet the need. When using serverless, applications run only when there is traffic, so your business pays only for the resources it uses. With containers and virtual machines, you pay for those resources to be available around the clock.

Building serverless architectures allows developers to focus on their applications instead of the minutiae of managing and operating servers or runtimes. This reduction of ancillary work lets developers save time while working and innovating in the cloud.

Benefits of serverless include:

  • Increased availability

  • Effortless scaling

  • Dedicated focus on functionality, not maintenance

2. Containerization

Containers provide a standard way for developers to package and deploy your application code, configurations and dependencies (such as monitoring or security frameworks) into a single object. It’s similar to the way a virtual machine may contain a virtual hard drive, operating system and applications. Containers let software run reliably when moved from one computing environment to another. Everything an app needs to run is in the container. Some of the most common uses of containers include building and deploying microservices, running batch jobs for machine learning applications and moving existing applications into the cloud.

Containerization can be useful when a company decides to modernize .NET Frameworks running on Microsoft Internet Information Services (IIS) to .NET Core 3 on Linux containers. Containers are also ideal for organizations that don’t want to start over rewriting their apps into AWS Lambda, for instance. Using containers, companies can pull apart their monolithic code into smaller pieces that can execute independently.

Containers are more suitable to companies that need the flexibility to install and use software with specific version requirements. With containers, you have full control of the installed programming language and runtime version with containers. That allows applications to be moved quickly between host servers—which is extremely useful when migrating legacy applications to the cloud, because it enables developers to replicate an application’s original running environment.

Benefits of containerization include:

  • Increased portability

  • Consistent operations

  • Enhanced developer productivity

3. Cloud-native re-platforming 

The re-platforming approach consists of moving your applications almost as-is, while replacing some components to take advantage of the cloud. Common modifications include transforming the way a program interacts with the database, so it can benefit from platform services that enable better scaling and higher availability in the cloud environment. This approach can allow infrastructure teams to focus on higher value-added services for the business.

Re-platforming of databases is a common approach to modernization for businesses. Some companies will even look at switching to an open-source database engine to replace costly licensed alternatives. When re-platforming database workloads, the goal is to release the organization from the day-to-day care and feeding of the database. 

Benefits of re-platforming include:

  • Added cloud-native functionality

  • Increased availability

  • Lower cost

In the next article in this series, we explore how to go from idea to market faster with serverless technology.

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PwC and AWS are helping companies modernize in the cloud.

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Scott Weber

Managing Director, Cloud & Digital, AWS Ambassador, PwC United States


Bob Moore

Principal & AWS Practice Leader, PwC United States


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