[whateveracct]

In Haskell vs other languages, a large amount of your program is written using various forms of composition (function composition, applicative/monadic composition [sequencing of side-effects], monoidal composition [combining values], library-specific composition [e.g. Conduit =$=] etc).

The stuff you compose tend to be small functions that are easy to test & reason about.

The nice thing about composition in Haskell is that if you have correct program A & B, then the composition of A & B is also correct & easy to reason about.