There are a lot of niche haskell blogs with some amazing posts. An random example I’ve gotten a lot out of is A Tiny Compiler For A Typed Higher Order Language. What are your favorites?
I like posts that do a different take on Haskell or Haskell concepts, e.g. Imperative Haskell by Vaibhav.
I have a few:
Programmatic translation to iteratees from pull-based code (2011) by Paul Chiusano.
Describes a method for transforming pull-based stream consumers into push-based ones.
Functor-Oriented Programming (2017) by Russell O’Connor.