> Yes, I really need a real word Haskell project simple enough to understand all the math concept There actually is a book with precisely that title, which provides what you're asking for: https://book.realworldhaskell.org/ > Like, I don't know when to implement the Monad type-class to my domain data types A concrete type (such as your Tweet type) can't be a Monad. Monad is implemented on generic types (think:... - Source: Hacker News / about 1 month ago

The Real World Haskell book is also outdated, but can also be read online for free, and has many examples and exercises on writing practical and usable applications. Although I have not read the book to the fullest, I still recommend its monad transformers chapter, as it was the one that made it click for me. - Source: dev.to / over 1 year ago

Stage 2: Advanced topics - Real World Haskell - Haskell in Depth. Source: over 1 year ago

I also liked https://book.realworldhaskell.org/ since it layers up to (wait for it) real world problems e.g reading a barcode from an image. I'm old so the O'Reilly format has a warm place in my heart. More textbooky. Source: about 2 years ago

So we have LYAH, also there is O'Reilly book, which is a bit old but still mostly good, many people start with this book. After any of those three you can probably decide for yourself what to use to continue the study. Source: over 2 years ago

I also looked into Snap (http://snapframework.com/) and Yesod (https://www.yesodweb.com/) for Haskell. I didn't really get anywhere with those though because I had build issues with dependencies and was in a bit of a hurry so I put them off for later. Source: almost 3 years ago

As with most languages, there are several good web frameworks. See for instance snap. Source: almost 3 years ago

Snap (http://snapframework.com/) and Scotty (https://hackage.haskell.org/package/scotty) are both projects that can fit this description. Source: almost 3 years ago