Programming Clojure, 2nd Edition

Optimizing for Performance

In Clojure, it is idiomatic to call Java using the techniques described in ​Calling Java​. The resulting code will be fast enough for 90 percent of scenarios. When you need to, though, you can make localized changes to boost performance. These changes will not change how outside callers invoke your code, so you are free to make your code work and then make it fast.

Using Primitives for Performance

In the preceding sections, function parameters carry no type information. Clojure simply does the right thing. Depending on your perspective, this is either a strength or a weakness. It’s a strength, because your code is clean and simple and can take advantage of duck typing. But it’s also a weakness, because a reader of ...