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My Experience Talking at JConf Colombia

·790 words·4 mins
Alejandro Duarte
Alejandro Duarte
Alejandro Duarte is a Software Engineer, published author, and award winner. He currently works for MariaDB plc as a Developer Relations Engineer. Starting his coding journey at 13 with BASIC on a rudimentary black screen, Alejandro quickly transitioned to C, C++, and Java during his academic years at the National University of Colombia. Relocating first to the UK and then to Finland, Alejandro deepened his involvement in the open-source community. He’s a recognized figure in Java circles, credited with articles and videos amassing millions of views, and presentations at international events.

Ever since I joined the team at Vaadin I had wanted to showcase our technologies at a local conference in my home country, Colombia. This year, the organizers of JConf Colombia 2019 invited me over to give not one but two talks during the event. It was good timing–the conference took place around the summer vacation time I had already planned to have in Colombia (I’m based in Finland).

JConf Colombia 2019 speakers

So, I packed my suitcase with the usual essentials, plenty of Finnish treats (read, salmiakki) and a bunch of Vaadin stickers and T-shirts. Unfortunately, this swags didn’t make it to MedellĂ­n (where the conference took place) since I know quite some people in the IT industry in Bogotá, where I initially landed in Colombia. Vaadin T-shirts are super popular! So, blame my IT colleagues in Bogotá if you didn’t get one at the conference. Kidding. It was bad planning from my side, sorry. Catch me at the next conference I’ll get you one.


I headed to MedellĂ­n two days before the conference started and was picked up at the airport by Geovanny Mendoza, a fervent Vaadin fan to whom I’m more than grateful. He has also been talking about Vaadin in other versions of the Latin-American JConf conferences. We spent the rest of the day talking about technology and the promising future of Vaadin.

Geovanny and Alejandro

The next day, I visited IBM Colombia and presented Vaadin and its philosophy–code your web UI in Java without JavaScript or HTML. Most of the audience didn’t know about Vaadin at all. They looked impressed by how fast you can get started with it. The code, to them, resembled the API of Java’s Swing, which many developers used when they were learning Java. However, it was an eye-opener to realize that the younger developers didn’t know about Swing nor had used it before. And even so, they were easily guessing the names of the Vaadin API’s methods I had to use while coding.

Alejandro Duarte presenting Vaadin

The first track of the conference started the next day. It was held in the theater of the University of Antioquia which has a capacity of more than 1000 people. Talks were mostly technical but there was an emphasis on community and open source.

Speakers photo

My first talk at JConf Colombia, Colombians in the Open Source World: Our Experience Working for Payara and Vaadin, was shared with the talented Fabio Turizo, also Colombian, and a Java Architect and Developer working as a Service Team Manager for Payara. I hope we can do additional collaborative work in the future with Fabio and Payara’s technologies.

Fabio from Payara

In our talk, we shared our experience working for open-source companies. What are these companies all about? What products do they develop? How did we end up working there? How is it to work for these companies? What do we do at these companies? It was fun to share this kind of insights, and since Vaadin is so simple to use and everybody in the audience was a developer, I managed to explain what Vaadin is in a single slide with a “Hello, World” application. After the talk, I was amazed by some developers in the audience who approached me to ask more about Vaadin, both the company and the web framework.

The second track was on the next day at Ruta N Complex. A day packed with amazing international and national speakers with highly technical topics. I quickly prepared my laptop for my talk Implementing Modern Web Pages in Java and got the chance to talk about the very origins of the Spring + Vaadin integration with its own creator Josh Long from Pivotal before heading to the auditorium.

Alejandro Duarte and Josh Long

During my talk, I implemented a simple “comment system” from scratch. Developers were amazed by how you are able to leverage the full potential of a Java IDE (I used IntelliJ IDEA) while coding the presentation layer of an application with Vaadin. It was marvelous to see “wow” reactions during my talk.

Alejandro Duarte presenting Vaadin

After a couple of silly jokes, refactorings, and fun with Java code, we continued having conversations with developers who, again, wanted to know more about Vaadin. They were curious about how to integrate web components, how to organize or modularize the code, and how a company that releases an open-source free product makes money.

Group photo

I had a blast at the conference. Finally got to meet face-to-face Reza Rahman from Microsoft, and Josh Long and Mark Heckler from Pivotal. Plenty of “wow” reactions during my talks which was a nice reminder that we are developing a really cool technology at Vaadin. Thanks for the inspiring discussions to the people from Payara, IBM, and Jakarta EE and all the organizers of the event. I’m definitely looking forward to joining the 2020 edition!


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