diff --git a/CLAUDE.md b/CLAUDE.md
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+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Build & Test Commands
+
+This project uses pnpm (v10+) and requires Node.js >= 20.
+
+```bash
+pnpm install          # Install dependencies
+pnpm build            # Compile TypeScript (uses tsdown)
+pnpm test             # Run Jest tests
+pnpm pretty:check     # Check Prettier formatting
+pnpm pretty:fix       # Fix formatting issues
+```
+
+To run a single test file:
+```bash
+pnpm test src/__tests__/rss2.spec.ts
+```
+
+## Architecture
+
+This library generates RSS 2.0, Atom 1.0, and JSON Feed 1.0 feeds from a common data model.
+
+**Core Pattern**: The `Feed` class (`src/feed.ts`) stores feed configuration and items. Three renderer functions transform this data into different output formats:
+
+- `src/feed.ts` - Main Feed class with `rss2()`, `atom1()`, `json1()` methods
+- `src/rss2.ts` - RSS 2.0 XML renderer
+- `src/atom1.ts` - Atom 1.0 XML renderer
+- `src/json.ts` - JSON Feed 1.0 renderer
+- `src/typings/index.ts` - TypeScript interfaces (Item, Author, Category, Enclosure, FeedOptions)
+
+**Dependencies**: Uses `xml-js` for XML generation. Path alias `@app/*` maps to `src/*`.
+
+**Testing**: Jest with snapshot testing. Snapshots in `src/__tests__/__snapshots__/` ensure output consistency across formats.
diff --git a/package.json b/package.json
index bc9c623..8138acb 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "feed",
-  "version": "5.2.0",
+  "version": "5.2.1",
   "type": "module",
   "description": "Feed is a RSS, Atom and JSON feed generator for Node.js, making content syndication simple and intuitive!",
   "homepage": "https://github.com/jpmonette/feed",