K is not an esolang and was not designed for golf; it has real users. https://en.wikipedia.org/wiki/K_(programming_language) https://en.wikipedia.org/wiki/K_(pr

K is not an esolang and was not designed for golf; it has real users. https://en.wikipedia.org/wiki/K_(programming_language) https://en.wikipedia.org/wiki/K_(programming_language) Also, the primary goal is not always speed... runtime speed or speed of development. There are other things we trade off for all the time.