For the third year in a row, I had the chance to attend Devfest Toulouse. The opening word was done in the style of an Apple Keynote, to highlight how the event grew in size over the years. The thing with Devfest Toulouse is that it gathers the entire software related ecosystem in Toulouse area. As such, it is the perfect place to catch up with former colleagues and friends.


The conference really started with a keynote by Fabien Tregan, about the history of computing devices. From basic tools to help counting to more sophisticated machines, Fabien tells us a part of History. An entertaining way to start the day.

I attended several talks in the morning but only the one by Gauthier Mechling, about micro-controllers and iot really caught my attention. Gauthier is an excellent speaker (well prepared and well organized, having backups when a demo fails, uses the webcam to show us tiny chips,...) and he shares greatly his passion for IOT. His talk while not at all related to work was inspiring. The other ones, were, imho not versed into code and were missing examples.

Before lunch, the lightning talk by Guillaume Andrieu about Jean-Yves Girard was an short introduction to the work of Jean-Yves Girard. A longer format would have been nice. It was (the only ?) a talk related to the academic world and I think it was important to have such a talk, at least to state how research affects our work (even if in the long run).

I found the afternoon much more interesting in terms of content with three awesome talks. Starting with Steve Klabnik who talked about Rust and WASM (Web ASeMbly). The main point was to highlight how a browser is similar to an operating system and how WASM could be the future of serverless. This is funny as some weeks later, Clever Cloud folks did a presentation introducing their FaaS feature which is built exactly on WASM.

Then, François Techeyne shared with us his thoughts about the concept of errors. He highlights how error design is important and even valuable. In microservices environments, it is even more useful to contextualize errors. The context can be used by support teams to quickly track errors on customer request, for instance. In the end, this talk shows how errors are a part of a system, and how they can help us improve a system but also an organization (and this goes far beyond software imho). Go watch it as it is fundamental!

Last but not least, I attended an introduction to Constraint Programming by Cyril Delmas. Before the conference, it was the only talk I had check as "must attend", as I thought about Constraint Programming to solve a scheduling problem (more on this later, maybe). Cyril just gave a perfect introduction to this topic, showing us some examples with a gradually increasing complexity. Bonus point, he used a solver, OscaR written in Scala. In the end, his talk was a lot about "how to model a problem so that we can solve it with Constraint Programming".


Devfest Toulouse isn't just about talks. It is the opportunity to meet new people and to reconnect with former co-workers and friends. And the staff is well aware of it so a lot is put in the "context" and logistics to encourage this. The venue is the best you can have in the city center of Toulouse (I mean, close to the railway station, with the subway nearby,...). Food is also good with breakfast / lunch and a special care to vegetarian people. Everything is put in motion so that you can talk to sponsors and interact with other attendees.

The organization is clockwork. Cloakroom, in the entrance, optional goodies bag (this one is an appreciable innovation from this year) and a warm welcome is what you get as soon as you pass the gates. No doubt the work backstage is huge: website is great, there is a multiplaform app to check the schedule, videos of the talks are online a few weeks after the event,...

Personal takeaways

Don't get me wrong, DevFest Toulouse is an incredible event powered by an awesome team of volunteers (not paid to do that, just to stress that again). But I somehow find it less and less about development (as stressed in the title, it is more a TechFest now). The good thing is that there are less talks whose purposes are to sell a framework (ie there are less Dev advocates/evangelists than before) but to actually present something (share thoughts about some problem, introduce something like the history of x, show results of an experiment,...). I know the audience is too large and diverse so talks like "Deriving typeclass instances in Scala" are relevant to only 10 attendees yet, I feel like there is some room for more advanced talks. Or workshops.
I still think that there is a missed opportunity in the DevFest to share fundamental ideas about programming between the different communities in Toulouse. I am not sure how this could work though... Yet, some talks were going in this direction. Or may be I am just having a mixed feeling about the content selection and just wished it to be more "advanced". It is also possible that some of the talks I wanted to see were overlapping.

In the end, from this year I take home some great talks and a running reasoning/meditation about errors, some stuff to try at home: ESP32 & Constraint Programming (not together !). As always it was good to see how diverse (in terms of technologies, not in terms of genders) the tech community is in Toulouse.

Every year I wonder if I should come back, but I always buy a early bird ticket so it is very likely that I will do so next year !