Juan Valdivia

Software engineer. Writing about systems, tooling, and the craft of building things.

Latest Post

April 10, 20264 min read

How I extended Claude Code with a custom skill that captures, diffs, and annotates Node.js performance snapshots directly in my editor workflow.

Performance snapshot skill for Claude Code

A custom CLI skill that captures Node.js CPU profiles, diffs them across runs, and surfaces annotated analysis inline in your editor.