1 min lesson
Reverse-ETL, briefly
Connect "Reverse-ETL pushes the modeled result back out" to the decision you would make.
Step 1 of 2
Reverse-ETL, brieflythe gold layer flows back out
Most pipelines pull data in to model it. Reverse-ETL pushes the modeled result back out: a churn score computed in gold lands in the CRM so a rep sees it, or a usage tier syncs to billing. It closes the loop so the data platform drives operational tools as well as dashboards.
When you get the build-vs-buy question, walk the framework before you name any tool, then split by layer: "Buy connectors for third-party SaaS, but build first-party ingestion at our scale because that's the differentiator and a commodity tool could cap out." Naming the exception, the one place you'd build against the default, is what shows judgment rather than a memorized preference.
The trap for a strong engineer is building things that should be bought because building is more fun. At a tiny early team, every week spent reinventing a Fivetran connector is a week not spent on the lakehouse only you can build. Bias to buy the commodity; spend your scarce build budget where it compounds.