The Reflex Architecture

YOW! Lambda Jam 2019

(Note to the reviewers: This is the same talk as my other submission, but with an added workshop that I could pair the talk to. I submitted in duplicate to make it clear that I'm up for doing the talk or doing a full combo if you think the workshop sounds like it is a good fit. As the proposals overlap, it only makes sense to accept one.)

Reflex-dom is a remarkably awesome way to write frontend web applications in Haskell. Reflex DOM is built from Functional Reactive Programming (FRP) primitives defined in a library called Reflex.

Writing apps in reflex-dom is a little weird at first because it's a whole brand new paradigm to structuring your programs. Just like the jump from imperative programming to FP, jumping into FRP is a tricky process of rewiring your brain to fit the new model of thinking. It can be very difficult to appreciate the power and architectures that you can from this transition while you are still learning the basics, which naturally makes it difficult to be motivated to put in the work.

The talk intends to help break this deadlock by talking about some high level reflex architecture that should be very familiar to anyone who has built a Redux or Elm app before. We'll explore the mtl style constraints that reflex offers for state management and the awesome things that this means for your programs and ability to reason about the type signatures of your widgets. You won't come away from this talk an expert and ready to write a greenfield reflex app, but you should get an appreciation of the power reflex has to offer and a motivation to learn more!

In the workshop we will implement parts of the "real world demo", a demo blogging application designed as a way to test frontend frameworks with things like backend calls and frontend routing. There will be a lot of skeleton and example code already written and be very directed, so it's -- as with the talk -- it is going to be more getting a high level feel than learning all of the fundamentals. It is the hope that the fast paced guided intro will allow you to do the rest of the learning at your own pace later.