three-layer VS lox-haskell

I’m working on this pet project for a time now. Initially based on the three-layer repository, it’s now modelled after the Clean Architecture. In my understanding, it’s an OOP variation of the functional “Functional Core, Imperative Shell” approach. As most examples for Clean Architecture are written in C#, my module structure also looks more like a typical C# than Haskell one to me.

I personally use servant whenever i need networking. Altough scotty is easier/simpler, I would start with scotty. Aeson for JSON encoding/decoding. Actually! As i am writing this I would recommend a book (no its not a dry boring book, more of a tutorial) that implements a CI server from scratch. It’s vety descriptive and will show you the haskell ecosystem quite clearly: https://marcosampellegrini.com/simple-haskell-book. Seriously, it’s a damn good book and that’s how i learned haskell! Back to the libraries/ecosystem, if you want to learn how to use an app monad and mtl, these who come to mind: https://github.com/Holmusk/three-layer and https://www.parsonsmatt.org/2018/03/22/three_layer_haskell_cake.html. Under the github repo, check out the App folder to get a notion of how an app monad can be used. Personally I like mtl over monad transformers such as readerT. Best of luck!

I usually make web apps in haskell + react, when i started out learning haskell I found it invaluable to find a opinionated stack to learn about the ecosystem and to see "how to get things done". When i was learning haskell I really appreciated an example like: https://github.com/Holmusk/three-layer, essentially a "best practice" web app. Anyone in the clojure(script) community that can recommend some templates/examples to get to know the ecosystem? Since im comfortable with react im assuming clojurescript with re-frame/reagent makes sense for the frontend? So far i've only seen ring/jetty for the backend. To be clear, im not necessarily looking for the "simplest" frameworks but rather something that is highly reliable in production. The backend will expose simple JSON crud with some endpoints being quite computationally heavy (concurrency will be important).

In Haskell, Matt Parsons popularised the Three Layer Haskell Cake (2018). Holmusk (well, Kowainik) made this picture to go along:

If you feel like comparing implementations, you might want to take a peek at my implementation: https://github.com/Martinsos/lox-haskell -> I haven't finished the book unfortunately but I did all the work till chapter 9.5 -> each commit is marked with the chapter it implements, so you can easily follow the development that way. If you do make significant progress, do consider opening an issue on my repo to share your work, I would also love to do some comparison in order to learn more!

Very cool! More than a year ago I started going through Crafting Interpreters and implementing it in Haskell as I go, here it is in case you find it interesting: https://github.com/Martinsos/lox-haskell .