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Design ETL Pipeline for Exactly-Once Processing

HardPipelines00:00
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Problem

Context

FinTechCorp, a financial services company, processes millions of transactions daily. Currently, their ETL pipeline employs at-least-once semantics, leading to duplicate entries in their data warehouse (Snowflake) and complicating downstream analytics. The VP of Data Engineering has mandated a redesign to achieve exactly-once processing semantics to enhance data integrity and reliability.

Scale Requirements

  • Throughput: 1M transactions per second during peak hours.
  • Latency: Data should be available for querying in Snowflake within 2 minutes of ingestion.
  • Storage: Approximately 20 TB of data daily, requiring efficient storage management and cost control.

Requirements

  1. Implement a streaming ingestion layer that guarantees exactly-once delivery of transaction records.
  2. Utilize a message broker (e.g., Apache Kafka) with idempotent producers to prevent duplicates.
  3. Design a transformation layer that applies business logic while maintaining data integrity.
  4. Ensure data is loaded into Snowflake with proper deduplication and error handling mechanisms.
  5. Establish monitoring and alerting for data quality issues, including duplicate detection and processing failures.

Constraints

  • Team: 5 data engineers, limited experience with Kafka.
  • Infrastructure: AWS-based, leveraging existing resources (EC2, S3, Snowflake).
  • Budget: $30K/month for cloud services, including storage and compute.