# A multi-tenant SaaS platform ingests from many sources, has a legacy dual-write inside its order ser Canonical URL: Domain: Pipeline Design ยท Difficulty: medium ## Problem A multi-tenant SaaS platform ingests from many sources, has a legacy dual-write inside its order service, serves three downstream consumer teams, and has weathered a flash sale that revealed it has no backpressure handling. Compose the resilient ingestion. Replace the dual write with the transactional outbox and a Debezium-driven publisher. Add a durable buffer between producer and consumer with a named depth and overflow strategy. Add resource isolation by tier with a per-tenant lag monitor. Each sink dedupes on a stable key. The three downstream consumers continue to receive events through the new outbox-fed Kafka topics. ## Related - [All practice problems](https://datadriven.io/problems) - [Mock interview mode](https://datadriven.io/interview/a-multi-tenant-saas-platform-ingests-from-many-sources-has-bdd99933) - [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.