keywordize-keys currently takes a single argument, a nested structure presumably containing maps, turning all string keys into un-namespaced keys. I've found that I've needed to maintain my own modified version of keywordize-keys that allows me to pass a namespace so I can import JSON objects and use them with clojure.spec (which strongly prefers namespaced keys).
The addition of an additional 2-arity invocation with a namespace string argument is a non-breaking change. I'll attach a patch once I have a JIRA number.
This patch also includes a test but I accidentally selected "Code" when I opened the ticket. I don't think I can change that. Can a maintainer update the "Patch" field to "Code and test"?
Another route to go with this btw is to first do to build on.