Lambda World Cadiz 2019

After a stellar experience last year where I was invited by 47degrees winning a golden ticket at Scaladays, I decided to come back to Cadiz for the 2019 edition as well. This blog posts gives you some insights into my experiences and hopefully convinces you to join next year as well.

Travel

Cadiz is a bit hard to reach coming from an international destination. Closest airport is located near Jerez, but this year we decided to fly to Sevilla, spend some hours there and then go to Cadiz by train. The train took roughly 90 minutes and was a very pleasant experience. If you were wondering about the “we” mentioned earlier: Kirill (@darkiri), Andy (@_andys8) and me formed a travel group booking the same flights and hotel.

Cadiz

On the first evening we were hanging out with some other Autoscouties who arrived earlier than us + some other colleagues from Barcelona. Cadiz is a lovely town, which offers a lot of places to have good food and enjoy some drinks and this is exactly what we did.

Day One

The first day started off with the unconference, which I spent mostly in the hallway, since I met some people who I had not seen for ages. The workshops started right after the unconference. Note that I’m not very excited about large group workshops, which also are very time limited as well.

Adam Rosien managed to overcome this and raised some interest in me to look a bit deeper into Property Based Testing. Unfortunately the session was too short to really go into deep and answer the interesting questions of how to write good property based tests for real world programs.

The second workshop was about the Mu framework developed by some employees of 47 degrees. Its goal it is to enable writing microservices in an api-first, functional way. While Mu certainly looks interesting, the workshop itself suffered from some technical issues and again the huge audience / short timeframe factor.

The first day was closed out by an excellent keynote of Martin Odersky on Design Mistakes of Scala implicits and how they fixed them in Scala 3. I highly recommend watching the video to any Scala developer. Bonus points here: He sneaked in braceless syntax on the slides and was smiling like a child when someone from the audience recognized it.

After the conf it was time to enjoy the sunset at the beach and afterwards hanging out in one of the excellent tiny food places in Cadiz with my coworkers from Autoscout24.

Day Two

I was really looking forward to the talks day and was not disappointed. While the keynote was very mathematical, Emily Riehl was quite well explaining some linkages from mathematics / category theory and functional programming. Afterwards the audience splitted up to two seperate tracks. I will be covering the talks I decided to enjoy.

The first one was Aditya Siram explaining static introspecition capabilities in languages such as D and Nim. The features shown in the talk seem to be very useful, most prominently executing code at compiletime. It was very refreshing to get a glimpse into this style of programming and also seeing the potential it has.

Afterwards I joined Raul Raja and Simon Vergauwen who were showing off there work on the Arrow metacompiler for Kotlin. Everything shown in the talk looks very intriguing, especially the possibilities this enables for tooling and integration into IDE. Most prominent one was that the IDE could point out a sideeffect which wasn’t wrapped into an IO. I will definitely keep this and Kotlin on the radar.

The Erlang presentation of Laura Castro had the advanced seal on it, but in the end it was a very accessible introduction to Erlang + property based testing Erlang applications. It became immediately apparent that Laura is an experienced teacher, since her explanations were on point and the talk was easy to follow + the story was well built up.

Before the lunch break, I joined April Goncalves for their talk about optimizing code with math. It was cool to see some tricks for code optimization and their favorite topic: art programming.

During lunch break Chris ford was showing off some algo music live coding, which immediately gathered a huge crowd. Seeing him and his Leipzig library in action was an inspiring moment for everyone around.

Back to the talks: I joined Laura Bocci for a presentation on her research on time-sensitive protocols. To be honest: I did not understand everything there and probably have to re-watch the video on this one.

After this rather theoretical one, J Heigh was showing off some fp in Rust. It was very interesting to see some Rust, since I personally haven’t had looked into it in great detail in the past. My takeaway here: It’s possible to program in a FP style in Rust, but the language itself is very mixed paradigm.

After a quick coffee break, Robert Avram showed a great performance with his story about “A series of unfortunate effects”. To really understand the greatness of this talk you have to take performance and story very literal. He was telling the story of the battle between the programmer and the effect in a wizard, castle, raven setting backed by nicely designed slides with silhouette art. He confessed afterwards that he is a GIMP pro now. The content of this talk was on point as well, since it showed the evolution from concrete effects such as Maybe over Free, Freer towards Eff. Everything was backed by examples showing the intuition behind the effects. I really enjoyed this one and hope that the video can preserve the magic in the room. For sure one of the best talks I’ve watched in the last time.

Closing the conf was Em Grasmeder from Thoughworks explaining some concepts of data science on the example of a cholera outbreak in London in the 18th century. It was a really inspiring keynote showing what data science is about from their point of view. I could agree on most of the points made, especially the ones surrounding keeping the business value in the mind. Most businesses do not need complex models, they need answers to their business questions. Bonus points for shouting revolution in the end and encouraging people to think about whether the company they work for is evil.

Closing words came from Jorge, one of the organizers of the conf, bringing his son Momo to the stage. This really shows the attitude and spirit of the conference. They are trying to create a very familiar atmosphere and have succeeded again. I’m pretty sure that most participants will show up next year again.

After the official ending there was the obligatory party at the castle, this year with two rock bands. Unfortunately the music was too loud for me, so I grabbed my coworker Diego to enjoy the atmosphere on the streets of Cadiz on a warm friday evening.

Verdict

People who come to Lambda World Cadiz always come back. I haven’t regretted my second visit and probably join this awesome conference next year again. Huge thanks to Jorge, Benjy, Maureen and everyone else involved for organizing this event and making it this the best place to be in October.

Personal blog by Martin Lechner
Thoughts about (functional) programming