clojurescript-cross-platform-code

To write cross-platform ClojureScript code, use `.cljc` files combined with reader conditionals like `#?(:cljs ...)` and `#?(:clj ...)` to handle platform-specific logic. This allows identical execution on both the JVM and JavaScript environments.

Use the `.cljc` file extension when you need cross-platform ClojureScript code that runs on both the JVM and browser. Files with `.clj` are for JVM-only, while `.cljs` is for browser-only execution.

Yes, you can run frontend ClojureScript unit tests on the JVM. This approach leverages faster execution and standard tooling, enabling a JVM TDD workflow for business logic, state management, views, and actions.

The best way to share logic is writing universal ClojureScript code in `.cljc` files. This creates a shared library that both backend Clojure APIs and frontend ClojureScript applications can use without duplication.

Reader conditionals use `#?(:cljs ...)` and `#?(:clj ...)` syntax within `.cljc` files to evaluate platform-specific code blocks. This mechanism ensures the compiler only processes the code relevant to the targeted JVM or JavaScript environment.

Yes, a JVM TDD approach works for testing views and actions. It enhances testability and development speed by allowing you to unit test frontend business logic and state management directly on the JVM.