Building an Automated KDP Pipeline: How I Engineered a Passive Income Stream with GPT-4 and n8n

What if your weekend automation project could pay for its own infrastructure and generate passive income? Last quarter, my book-generation pipeline cost $127 in OpenAI API calls and generated $4,200 in Kindle Direct Publishing (KDP) royalties—without me writing a single manuscript.

This isn't about "get rich quick" schemes. It's about applied automation engineering. Here's how I architected a serverless publishing pipeline that transforms API calls into royalty streams.

The Architecture

The system follows an ETL pattern adapted for content generation:

Ingestion: Niche research via SerpAPI/Google Trends