In Part 1 - Building a $0 Data Lakehouse with Apache Iceberg, Nessie, Neon, and Cloudflare R2 , we set up the infrastructure — a Nessie catalog on Fly.io, Neon PostgreSQL for metadata, and Cloudflare R2 for object storage. All on free tiers. Now comes the interesting part: actually loading data into Iceberg tables . In this article, I'll walk you through a Python-based approach that: Reads CSV fil