# A real production diagram with four sources, a layered architecture, and two consumers is on the can Canonical URL: Domain: Pipeline Design ยท Difficulty: medium ## Problem A real production diagram with four sources, a layered architecture, and two consumers is on the canvas. The section named five annotations a complete diagram must encode; the boxes-and-arrows version already covers two of them. Add the section's third annotation (cadence) on each source so on-call can tell at a glance which source to investigate first when freshness is missed. At least three distinct freshness tiers should be visible across the four sources. ## Related - [All practice problems](https://datadriven.io/problems) - [Mock interview mode](https://datadriven.io/interview/a-real-production-diagram-with-four-sources-a-layered-archi-abcfbfb3) - [System Design Interview Questions](https://datadriven.io/data-engineering-system-design) - [Data Engineering Interview Prep Guide](https://datadriven.io/data-engineer-interview-prep) - [Daily Challenge](https://datadriven.io/daily) --- Source: DataDriven (https://datadriven.io). 100% free data engineering interview prep. Live code execution against Postgres 16, Python 3.11, and Spark sandboxes. No paywall, no premium tier, no signup gate.