Clj-kondo

A linter for Clojure code that sparks joy. Clj-kondo performs static analysis on Clojure, ClojureScript and EDN, without the need of a running REPL. It informs you about potential errors while you are typing. To detect lint errors across namespaces in your project, a cache is needed. To let clj-kondo know where to create one, make a .clj-kondo directory in the root of your project, meaning on the same level as your project.clj, deps.edn or build.boot. A cache will be created inside of it when you run clj-kondo. Before linting inside your editor, it is recommended to lint the entire classpath to teach clj-kondo about all the libraries you are using, including Clojure and/or ClojureScript itself. Since clj-kondo now knows about your version of ClojureScript via the cache, it detects that the number of arguments you passed to select keys is invalid. Each time you edit a file, the cache is incrementally updated, so clj-kondo is informed about new functions you just wrote.