Transducers are IMHO one of the most under-appreciated features of Clojure. Once you get to know them, building transducer pipelines becomes second nature. Then you realize that a lot of data processing can be expressed as a pipeline of transformations, and you end up with reusable components that can be applied in any context.

The fact that transducers are fast (you don't incur the cost of handling intermediate data structures, nor the GC costs afterwards) is icing on the cake at this point.

Much of the code I write begins with (into ...).

And in Clojure, like with anything that has been added to the language, anything related to transducers is a first-class citizen, so you can reasonably expect library functions to have all the additional arities.

[but don't try to write stateful transducers until you feel really comfortable with the concepts, they are really tricky and hard to get right]