July 13–16, 2020

Reactive in practice: Transforming a legacy app

9:00am–5:00pm Tuesday, 07/14/2020
Location: Portland 256

To attend, participants must be registered for a Training Pass. Please note: 2-Day Training passholders have access to TWO 1-day training courses, ONE on Monday and ONE on Tuesday. 1-Day Training passholders have access to ONE 1-day training course on Monday OR Tuesday.

So you're a developer, you've heard of reactive, and you're excited to see how you can use its guiding principles to make your application more responsive and resilient. Mary Grygleski and Grace Jansen walk you step-by-step through how to transform your application into a truly reactive system that gracefully handles failure, elastically distributes resources, and is responsive to your end users.

What you'll learn, and how you can apply it

  • Learn how to start to think "reactively"
  • Get hands-on experience implementing reactive microservices using a modern reactive library (such as Eclipse Vert.x or RxJava) and deploying a reactive system application onto a Kubernetes container-based environment running on an open cloud platform

Who is this presentation for?

  • You're a software developer or engineer or software architect.




  • A basic understanding of Java programming (version 8 or above)
  • A working knowledge functional programming, streams processing, and cloud deployment

Hardware and/or installation requirements:

  • A laptop with Java version 8 or above, a recent version of Docker, and an IDE or editor installed (A GitHub repository will be provided.)
  • A free IMB Cloud account (URL to come)
  • Follow additional setup instructions (links to come)

With the advances in hardware, containerization, and virtualization technology within the past decade, software such as reactive systems is catching up to take advantage. Implementing reactive systems and writing code using the reactive approach may sound difficult, but Mary Grygleski and Grace Jansen illustrate that this can be done in a very manageable manner. While a reactive system isn’t a “one-size-fits-all” cure to all problems, it does seem promising to be a solution to computing challenges such as system responsiveness, resiliency, and scalability.

You’ll learn how to transform a legacy, monolithic, on-premises application into a modern, highly responsive, microservices and cloud-based system. You’ll use the IBM Stock Trader application and build a few sample microservices using an open source reactive library (such as Eclipse Vert.x or RxJava).

Mary and Grace explore the Stock Trader application in its legacy monolithic form, which can only be deployed as an on-premises app, to help you understand the common issues that face a lot of the legacy applications today. You’ll discuss how to redesign the monolithic Stock Trader application and break up the different components of the system into microservices, using a reactive approach where appropriate. You’ll go hands-on with reactive implementation by selecting one or more microservices and work on their implementations with guided examples.

You’ll be able to deploy your transformed application to Minishift or OpenShift on an open cloud platform (such as IBM Cloud). For ease of deployment, you’ll have access to a fully implemented solution, so you can use any of the sample microservices you need, or simply take the entire sample application, in order to try out the cloud deployment.

About your instructors

Photo of Mary Grygleski

Mary Grygleski is a Java developer advocate at IBM, specializing in reactive Java systems. She started working as a software engineer with C and Unix, then got into Java, open source, and web development in the new millennium, and now she’s venturing into reactive, mobile, and DevOps. Previously, she worked for several technology product companies in the Route 128 Boston Technology Corridor, as well as the San Francisco Bay Area. She now resides in the Greater Chicago area, and is an executive board member and president of the Chicago Java Users Group (CJUG). She’s an active co-organizer for the Big Data Developers in Chicago, Chicago Cloud, and IBM Cloud Chicago meetup groups. Mary continues to be amazed by how software innovations can dramatically transform our lives. Despite the many challenges in an ever-evolving technical world, she gets energized by the constant change and believes that she has uncovered the pathway to staying young. She can’t wait to see what the next tech wave will be like.

Photo of Grace Jansen

Grace Jansen is a developer advocate at IBM, working with Open Liberty and the reactive platform. She’s been with IBM for a year, after graduating from Exeter University with a degree in biology. Moving to software engineering has been a challenging step for Grace, but she enjoys bringing a varied perspective to her projects and using her knowledge of biological systems to simplify complex software patterns and architectures. As a developer advocate, Grace builds POCs, demos and sample applications, and writes guides and tutorials to help guide users through technologies and products. Grace also has a keen passion for encouraging more women into STEM and especially technology careers.

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