// mix weights are our estimate from detected signal volume
The rare case where channel evolution is fully legible: 2020–2022, two years of daily LinkedIn posting with zero revenue (2k → 250k+ followers) while a staff data engineer at Airbnb → Mar 2023, quit and launched the paid bootcamp monetizing that audience → 2024–2025 added feeder channels: free YouTube bootcamps, the 43.7k-star GitHub handbook, Discord, Substack, milestone discount codes → peaked at $251k/mo (Dec 2025), then a sharp cohort-business contraction through 2026. One person's audience compounding into a $4.5M-all-time education funnel.
The primary channel is Zach Wilson's 528k-follower LinkedIn presence, built with documented volume ("I made 893 LinkedIn posts in 16 months") — follower milestones convert directly via promo pages like dataexpert.io/400k (40% off "to celebrate 400k followers").
Free 6-week bootcamps launched on YouTube funnel into paid cohorts — getting credit requires watching through the DataExpert.io platform, converting viewers into registered users ("I'm launching a free AI data engineering boot camp on Databricks on YouTube on August 3rd!").
The DataExpert-io/data-engineer-handbook repo (43.7k stars, 9.1k forks) is a curated everything-data-engineering resource whose README advertises the free bootcamps and pushes paid courses with discount code HANDBOOK10.
2.7k sitemap URLs — 1.3k /lesson pages and 1.3k /certification pages — with a discovery-call CTA and 75-seat cohort scarcity messaging on top of self-serve registration.
One email a week on how SaaS actually gets users — the new teardowns, what changed, and the founder claims our crawl just caught out. No fluff, unsubscribe anytime.