Notes after JavaDayIstanbul 2019

I remember that I wanted to study in Istanbul for my field back then, because I know most of the important events were hold in this city. So that could be beneficial for my technical and personal skills. Even though that was the motivation and I studied in Istanbul, unfortunately that is not what happened. Soon I found out that I could access the relevant content on the internet, even for the ones not taking place in Istanbul. Nevertheless, I attended a few community events and organizations. I could say that JDI19 brought back all of those thoughts and somehow satisfied that.


I stayed in track 2 (marmara 2) except the last talk.

javaday istanbul schedule

In recent project at work, we implemented some of principles from microservice architecture. As developers, we had full control just on test environment(other two environments being uat/prod). After some problems and number of services we had, I saw the need of having a dashboard telling us what is going on. I started with a simple status dashboard, and with the help of colleagues we created some other features. It was a start and it was a primitive project. So I was interested in Monitoring at Peak talk in order to see how it is done in real life. It was nice to hear their experience and the validation of that I need to take time and dig into Prometheus. Another important point from this talk was that it was the first time I heard about postmortem. Now I see that it was not a surprise to hear the same word in A Hitchhiker’s Guide to Serverless Computing while he was talking on SRE.

Prometheus Architecture @Peak

The next talk was Coroutines for Java Developers. I listen about coroutines from Kotlin a few times, I know about goroutines. This whole topic of multithreading, parallelism, asynchronous, reactive programming has much similarity with my experience with Trigonometry in high school, which I knew about but not comfortable with it until I did not have any chance but learn it as much as that it would not cause me problems in the university entrance exam. I keep an eye on those techniques but I will go full in depth when I will have a problem and its traditional solution will not be acceptable.

Another talk was from @yalcinyenigun on Scaling Payments in Black Friday 2018 (links to blog post). I picked this talked because I follow @iyzicoEng. They seem to have colorful team and environment. Learning a bit more on scaling is never a waste of a time neither. Again my experience with scaling is much like above mentioned topic(not to be surprised one is solution to another). It has not been a problem for me yet(not because I solved that problem, or do not care about the problem, but have not had a such traffic-or-resource-attracting project). It was my favorite talk at the conference.

Ten Common Mistakes Made in Functional Java by @BrainVerm was a refreshing and resting mind talk. We used Java 8 in the recent project at work. I was sad that I witnessed many of mentioned problems, at the same time I was happy that we implemented similar solutions to overcome them.

It would be such a miss if I would not attend one of the serverless talks. That was A Hitchhiker’s Guide to Serverless Computing by @alexismp. Mainly, they are called serverless, but there is a hidden server :). I like the pic-a-daily app he demonstrated. Simply you upload a picture, and vision api extract information from the pics and add tags to them. SRE was the main thing that I got from this talk. You can see other resources and two free books mentioned on the website. He put it SRE as follows:

public class SRE implements DevOps {}

The last talk was in Marmara 1 on A Deep Dive Into Progressive Web Apps by @cagataycivici. This talk had two important bits: first one was technical failure of devices for presentation, slides were once visible and the gone again and again(such a shame for such event). That did not ruin the talk though. He was calm and cool even when fighting to fix it. I admired his attitude, that he turned it into a comedy that we were all laughing. Second one was the topic. I did not know that PWA was the technology that I was looking for. There was a long time that I stopped developing Android mobile apps, but people are not happy even when the web application is mobile-friendly. They always request an application for their devices. In near future I was experimenting with React-Native for Todarch. When you are a single person in a project, it is too much of a divided effort(development, deployment, database, cli, web-ui, react-native). Finally, I decided to continue with only web application. This talk proved that I did not give up on too much, and give meaning to those extra bits in create-react-app project(to be honest once I was just deleting those manifest.json, serviceWorker etc). If I pay attention to some of the principles, the web application could be used as a mobile application, or even desktop application. I will take more time to learn and experiment with PWA.


I won a t-shirt from Jetbrains quiz, and got one with Java Day Istabul from the organization. So I have two black and nice t-shirts, cannot wait for the summer.

Our manager got a coupon(for asking a high-voted question) for a free book. We used it to have a general computer science book to refresh the fundamentals at work during breaks.

And finally, that is a picture of what I brought back home apart from the technical knowledge and awareness.

javaday istanbul schedule

jdi19 event

The location was the easily accessible and fancy. As you could see from my comments the content was satisfying (at least the ones I attended). The serving of food (breakfast, lunch, and other stuff) was great. My belly was satisfied as much as my brain. The companies in the hall had enough content to have fun and be busy with.

SliConf application was used during the sessions for asking questions. This is of course just one of the functionalities of the application. Even though, the application is not yet so smooth to use, the part for question did its job. People did not have to catch microphones, and the questions with high-points(+1 by other attendees) were answered by the speaker at the end of the session. IMO, that fixes some of the problems with the traditional concept:

I thank all people who made effort to make this event happen, and my manager for giving me the opportunity to attend, finally friends for making it more fun.

javaday istanbul schedule