Devnexus 2026

A Data-Oriented Programming Approach to REST APIs

Kenneth Kousen

Ken Kousen is the author of the Pragmatic Programmers books "Mockito Made Clear" and "Help Your Boss Help You", the O'Reilly books "Kotlin Cookbook", "Modern Java Recipes", and "Gradle Recipes for Android", and the Manning book "Making Java Groovy". He is a regular speaker on the No Fluff, Just Stuff conference tour, and has spoken at conferences all over the world. He is a Java Champion, a JavaOne Rock Star, and a Devnexus Rock Star. Currently he a Professor of the Practice of Computer Science and Associate Director for STEM Initiatives at the Entrepreneurship Center at Trinity College in Hartford,...

API Versioning in Spring

Spencer Gibb

Spencer Gibb is a Software Engineer at Broadcom where he is the co-founder and lead of the Spring Cloud Core projects. His interests include distributed systems, JVM languages, web services frameworks, message-driven architectures and making software development simpler. He has industry experience in early e-commerce platforms, government and non-profit organizations, and business intelligence startups. He has extensive java experience and experience in other languages such as scala and python.

Autoscaling Spring Boot apps in Kubernetes with KEDA

John Coyne

John is a Distinguished Engineer of Application Engineering at Discover (a division of Capital One) with over 21 years of experience developing Java applications. His current interests include Observability, CI/CD automation, Kubernetes, and good API design. Outside of work, John enjoys spending time with his wife and two boys, running, biking, and enjoying live music.

Beyond SWE-bench: Enterprise Java AI Agents and Real-World Development Benchmarks

Mark Pollack

Dr. Mark Pollack has been involved with the Spring framework since 2003, contributing core JMS functionality. He is currently leading the Spring AI project, which provides enterprise-ready abstractions for AI integration in Java applications. His Spring journey includes founding and leading several projects: Spring Cloud Data Flow, Spring XD, Spring Data, Spring Shell, Spring AMQP, and Spring.NET. Before his work with Spring, Mark was a post-doctoral researcher at Brookhaven National Laboratory, where he developed systems for storing and analyzing petabyte-scale datasets in high-energy nuclear physics.

Extend your JPA applications with Relational JSON documents

Anders Swanson

I'm here to help you use Oracle Database better, and more easily. As a Developer Evangelist at Oracle, I help developers build modern apps, including microservices, event-driven systems, cloud-native architectures, and more. If you're working with tools like Kubernetes, Spring Boot, or Kafka, and wondering how Oracle fits into that world, that's where I come in. My goal is to share practical, hands-on guidance that helps you build faster, ship smarter, and make the most of Oracle's database tech. If you're using JSON, event streaming, vector search, or just figuring out how to get started, I'm here to make things...

I Can See Clearly Now: Observability of JVM & Spring Boot 2-3-4 apps

Jonatan Ivanov

Jonatan Ivanov is an enthusiastic Software Engineer, member of the Spring Engineering Team, maintainer of Micrometer, one of the leaders of the Seattle Java User Group, speaker, author, Java Champion. He has hands-on experience in developing and shipping innovative, production-ready software for industry-leader companies. He likes Distributed Systems, Production, Open Source, Math, Linux, Cloud environments; he is passionate about the Java Ecosystem and the Java Community. He is an Open Source contributor, writes a "develotters"-focused blog (https://develotters.com), sometimes can be found on Twitter(@jonatan_ivanov) and in the Seattle area.

Java Performance: Beyond Simple Request Latencies

John Ceccarelli

John Ceccarelli has been been in the Java space for 25 years, from leading the engineering team behind NetBeans at Sun Microsystems to leading product management for Azul's high-performance Platform Prime JDK. He loves making complex technologies more accessible, whether it was EJB 2.0 back in the day to today's cutting edge JVM tuning technologies.

Simon Ritter

Simon Ritter is the Deputy CTO of Azul Systems. Simon has been in the IT business since 1984 and holds a Bachelor of Science degree in Physics from Brunel University in the U.K. Simon joined Sun Microsystems in 1996 and started working with Java technology from JDK 1.0; he has spent time working in both Java development and consultancy. Having moved to Oracle as part of the Sun acquisition, he managed the Java Evangelism team for the core Java platform, Java for client applications and embedded Java. Now at Azul, he continues to help people understand Java as well as...

Java's Asynchronous Ecosystem

Daniel Hinojosa

Daniel Hinojosa is a programmer, consultant, instructor, speaker, and author. With over 20 years of experience, he does work for private, educational, and government institutions. Daniel loves JVM languages like Java, Groovy, and Scala; but also works with non-JVM languages like Haskell, Ruby, Python, LISP, C, C++. He is an avid Pomodoro Technique Practitioner and makes every attempt to learn a new programming language every year. Daniel is the author of Testing in Scala and the video of Beginning Scala Programming Video Series for O’Reilly Publishing. For downtime, he enjoys reading, swimming, Legos, football, and cooking.

JUnit 6 + exploring the testing ecosystem

Jeanne Boyarsky

Jeanne Boyarsky is a Java Champion from New York City and has been a Java developer for more than 23 years. She has co-authored Wiley's Oracle Java 8/11/17/21 certification books in addition to "Real World Java". Jeanne volunteers at CodeRanch and mentors the programmers on a high school robotics team in her free time. She has spoken at numerous conferences including Dev Nexus, QCon, KCDC, and JavaOne.

Just-in-Time Compilation Isn't Magic

Douglas Hawkins

Doug has been working in the Java ecosystem for the past 20 years. First as a Java developer, then a JVM engineer, and now Java performance tooling at Datadog.

Make Mechanical Advantage YOUR Advantage: How to modernize & futureproof your code with OpenRewrite

Mark Heckler

Mark Heckler, MBA is the Senior Director of Field Engineering at Moderne. He has worked with key players in numerous industries and organizations to develop, deliver, and maintain critical capabilities securely, on time, and on budget. Mark is an open source contributor, author of Spring Boot: Up and Running (https://bit.ly/springbootbook), and a licensed, instrument-rated pilot.

Peek Inside Production JVMs for Full Insights

Bruno Borges

Greetings, I’m Bruno. I’m a Product Manager at Microsoft living in Vancouver, Canada. I am a fan of photography, technology, and movies. I’m also interested in food and travel. But most importantly, I'm opinionated!

Scotty I need Warp Speed - Ways to improve JVM startup

Gerrit Grunwald

Gerrit Grunwald is a software engineer that loves coding for around 40 years already. He is a true believer in open source and he is an active member of the Java community, where he founded and leads the Java User Group Münster (Germany), he is a JavaOne rockstar and a Java Champion. He is a speaker at conferences and user groups internationally and writes for several magazines.

Spring Data 4: Data Access Revisited

Chris Bono

Focused on Spring Data, Spring gRPC, and Spring for Apache Pulsar

Supercharge Your Applications with Java, Graphs, and a Touch of AI

Jennifer Reif

Jennifer Reif is a Developer Relations Engineer at Neo4j, speaker, and blogger with an MS in CMIS. An avid developer and problem-solver, she has worked with many businesses and projects to organize and make sense of widespread data assets and leverage them for maximum business value. She has expertise in a variety of commercial and open source tools, and she enjoys learning new technologies, sometimes on a daily basis! Her passion is finding ways to organize chaos and deliver software more effectively.

Erin Schnabel

Erin Schnabel (@ebullientworks) is a Distinguished Engineer and maker of things at Red Hat. She is a Java Champion, with over 25 years under her belt as a developer, technical leader, architect and advocate, and she strongly prefers being up to her elbows in code. Erin learns (and teaches) by coding ridiculous things, like "Monster Combat" (https://github.com/ebullient/monster-combat), an application that makes monsters fight each other to explore application metrics; and “Game On! Text Adventure” (https://gameontext.org) for exploring cloud native development.

The Self-Cleaning Castle: How Garbage Collection Works in Java

Renette Ros

Renette is a technical lead at Entelect with degrees in BIS Multimedia and BSc (Hons) Computer Science from the University of Pretoria. She specializes in backend Java and Kotlin development, with extensive experience in Spring Boot projects. Renette is passionate about resilience engineering—ensuring production systems stay up even in challenging situations—and is dedicated to elevating the women around her and within her teams. She thrives on sharing knowledge, mentoring others, and fostering growth within her teams. When she's not engineering solutions, Renette enjoys diving into fantasy novels and exploring board games.

To Java 26 and Beyond!

Billy Korando

Billy is a Java Developer Advocate with the Java Platform Group at Oracle. With over a decade of experience in Java, Billy brings a passion for helping developers find ways to reduce tedious work, such as project initiation, deployment, testing, and validation, through automation and adopting the latest features and tools in the Java ecosystem. Outside of work, Billy enjoys traveling, playing kickball, and cheering on the Kansas City Chiefs. Billy also co-organizes the Kansas City Java users group.

What Every Spring Developer Should Know About Jakarta EE

Ivar Grimstad

Ivar Grimstad is the Jakarta EE Developer Advocate at Eclipse Foundation. He is a Norwegian Java Champion and JUG Leader based in Sweden. Besides advocating for the Jakarta EE technologies, Ivar contributes to the Jakarta EE specifications and is the PMC Lead for Eclipse Enterprise for Java (EE4J). He is also one of the specification leads for Jakarta MVC and represents Eclipse Foundation on the JCP Executive Committee. Ivar is also involved in various other open-source projects and communities. He is a frequent speaker at International developer conferences.

What's new in Spring Boot 4.0 & what's arriving 4.1

Phil Webb

Phil Webb is the co-creator of the Spring Boot open source project and has been serving as the project lead since its inception in 2013. Phil is employed by VMware where he is fortunate enough to be able to work full-time on open source software.

Zero to C-speed with only Java

David Vlijmincx

I’m a software developer at JPoint who loves to use and find new techniques and pragmatically apply them.

Core java

Frameworks