WriteinaClick, an AI book-writing platform I designed and built solo, end-to-end. Web and mobile apps, an AI writing assistant (Robin) that suggests edits in the author's own voice, and a multi-agent layer that runs daily operations. ~500 writers in under 6 months, fully organic, with a 34-minute average session and 5 books already published. Stack is React, TypeScript, Supabase/Postgres, GCP, OpenAI and Anthropic Claude.