I am a Director and Senior Principal Software Engineer (Red Hat) at IBM, based in Lyon, France.

As an individual contributor, I focus on reactive systems and Java-based cloud-native technologies, contributing primarily to Quarkus, Mutiny, and Eclipse Vert.x.

I am the author of Vert.x in Action – Asynchronous and Reactive Java, published by Manning:

Before joining IBM through Red Hat, I was an Associate Professor of Computer Science and Engineering at INSA Lyon and the CITI Laboratory, where I held several teaching, research, and leadership roles.

My long-standing engagement in the Java community earned me recognition as a Java Champion.

Professional experience 👨🏻‍💻 #

• Since September 2025 — Director, Senior Principal Software Engineer (Red Hat), IBM
• April 2024 – August 2025 — Senior Principal Software Engineer, Red Hat
• October 2018 – March 2024 — Principal Software Engineer, Red Hat
• September 2016 – August 2018 — Delegation to Red Hat through INSA Lyon, contributing to Eclipse Vert.x
• 2009 – 2018 — Associate Professor (tenured) and Researcher, INSA Lyon – CITI Laboratory
• 2016 – 2017 — Scientific Deputy Manager, Spie ICS – INSA Lyon IoT Chair
• 2014 – 2017 — Deputy Director, CITI Laboratory – Industry and society relations
• 2012 – 2017 — Manager, IST program, INSA Lyon
• 2011 – 2015 — Contracting Technical Writer, Oracle Corporation
• 2004 – 2009 — Researcher and Lecturer, Clermont-Auvergne University (ISIMA) and the University of New South Wales
• 2003 — Intern, Michelin, Software Methods and Tools Group

Open source contributions ✨ #

• Mutiny — Reactive programming library for Java. Maintainer.
• Eclipse Vert.x — Reactive toolkit for the JVM. Core developer and maintainer.
• Quarkus — Kubernetes-native Java stack for cloud environments. Developer.
• Eclipse Golo — Dynamic JVM language. Creator.
• JooFlux — Dynamic aspect injection and live method patching for Java. Co-creator.
• IzPack — Cross-platform software installer. Founder (retired).

Selected publications 📚 #

These works highlight key aspects of my research and open source journey.
For a full list, visit my publications page.

• Julien Ponge, Arthur Navarro, Clément Escoffier, and Frédéric Le Mouël. Analysing the Performance and Costs of Reactive Programming Libraries in Java. REBLS ’21, ACM SIGPLAN International Workshop on Reactive and Event-Based Languages and Systems, 2021. DOI PDF
• Julien Ponge and Mark Little. Scalability and resilience in practice: current trends and opportunities. SRDS 2019, Lyon, France. PDF
• Stefan-Gabriel Chitic, Julien Ponge, and Olivier Simonin. SDfR – Service Discovery for Multi-Robot Systems. ICAART 2016, Rome, Italy. HAL entry
• Julien Ponge, Frédéric Le Mouël, and Nicolas Stouls. Golo: a Dynamic, Light, and Efficient Language for the Post-InvokeDynamic JVM. PPPJ’13, Stuttgart, Germany. DOI PDF
• Julien Ponge, Boualem Benatallah, Fabio Casati, and Farouk Toumani. Analysis and Applications of Timed Service Protocols. ACM Transactions on Software Engineering and Methodology, 2010. DOI

PhD supervision 👨‍🔬 👩‍🔬 #

• Arthur Navarro (defended 2025, Red Hat Research / ANRT CIFRE) — Choreography extraction and projection for the verification and the optimization of reactive distributed systems: a language-runtime continuum
• Patrik Fortier (defended 2024, INSA Lyon / Spie ICS IoT Chair) — Programming language abstractions for the Internet of Things. https://theses.fr/2024ISAL0039.
• Stefan-Gabriel Chitic (defended 2018, French Ministry Grant) — Middleware and programming models for multi-robot systems. https://theses.fr/2018LYSEI018.

Education 🎓 #

• 🇦🇺 PhD (under cotutelle agreements), University of New South Wales, 2008 — Supervised by Boualem Benatallah
• 🇫🇷 PhD, Clermont-Auvergne University, 2008 — Supervised by Farouk Toumani
• 🇫🇷 Master’s, Clermont-Auvergne University, 2004
• 🇫🇷 Bachelor’s, Clermont-Auvergne University, 2002
• 🇫🇷 High School Diploma, Lycée Alain Colas, Nevers, 1999