— name: clojure-write description: Guide Clojure and ClojureScript development using REPL-driven workflow, coding conventions, and best practices. Use when writing, developing, or refactoring Clojure/ClojureScript code. — # Clojure Development Skill ## Tool Preference When `clojure-mcp` tools are available (e.g., `clojure_eval`, `clojure_edit`), **always use them** instead of shell commands like `./bin/mage -repl`. The MCP tools provide: – Direct REPL integration without shell escaping issues – Better error messages and feedback – Structural Clojure editing that prevents syntax errors Only fall back to `./bin/mage` commands when clojure-mcp is not available. @./../_shared/development-workflow.md @./../_shared/clojure-style-guide.md @./../_shared/clojure-commands.md ## REPL-Driven Development Workflow – Start with small, fundamental functions: – Identify the core features or functionalities required for your task. – Break each feature down into the smallest, most basic functions that can be developed and tested independently. – Write and test in the REPL: – Write the code for each small function directly in the REPL (Read-Eval-Print Loop). – Test it thoroughly with a variety of inputs, including typical use cases and relevant edge cases, to ensure it behaves as expected. – Integrate into source code: – Once a function works correctly in the REPL, move it from the REPL environment into your source code files (e.g., within appropriate namespaces). – Gradually increase complexity: – Build upon tested, basic functions to create more complex functions or components. – Compose smaller functions together, testing each new composition in the REPL to verify correctness step by step. – Ensure dependency testing: – Make sure every function is fully tested in the REPL before it is depended upon by other functions. – This ensures that each layer of your application is reliable before you build on it. – Use the REPL fully: – Use the REPL as your primary tool to experiment with different approaches, iterate quickly, and get immediate feedback on your code. – Follow functional programming principles: – Keep functions small, focused, and composable. – Use Clojure's functional programming features—like immutability, higher-order functions, and the standard library—to write concise, effective code. ## How to Evaluate Code ### Bottom-up Dev Loop 1. Write code into a file. 2. Evaluate the file's namespace and make sure it loads correctly with: “` ./bin/mage -repl –namespace metabase.app-db.connection “` 3. Call functions in the namespace with test inputs, and observe that the outputs are correct Feel free to copy these REPL session trials into actual test cases using `deftest` and `is`. 4. Once you know these functions are good, return to 1, and compose them into the task that you need to build. ## Critical Rules for Editing – Be careful with parentheses counts when editing Clojure code – After EVERY change to Clojure code, verify readability with `-check-readable` – End all files with a newline – When editing tabular code, where the columns line up, try to keep them aligned – Spaces on a line with nothing after it is not allowed