A developer built a custom WordPress multilingual plugin in two days using Claude Code after Polylang broke their production blog. The plugin uses no custom database tables, relying on WordPress taxonomy and post meta instead. It supports AI-powered translation via Ollama, Anthropic, and Gemini, with URL prefixes, hreflang SEO tags, REST API filtering, and both Gutenberg and Classic Editor support. The post details the TDD approach (156 PHPUnit tests using real WordPress internals via wp-env), the AI translation prompt engineering to avoid AI-sounding output, and three production bugs Claude got wrong: taxonomy slug mismatch, replacing instead of merging tax_query, and OG meta tag conflicts with AIOSEO. Key lessons include deploying to production early, always merging query parameters rather than replacing them, and using curl to test as social crawlers would.