Building Data Pipelines at Scale: Lessons from Wayfair
Data Engineering
Back to Engineering Insights

Building Data Pipelines at Scale: Lessons from Wayfair

August 10, 2025
8 min read

How we process 800,000+ records daily with 99.7% accuracy using Apache Spark, Kafka, and cloud-native architecture at Wayfair.

The Challenge: Processing Millions of Records Daily

At Wayfair, we handle massive amounts of data every single day. With over 800,000 records flowing through our systems daily, maintaining 99.7% accuracy while ensuring real-time processing capabilities presents unique engineering challenges that require innovative solutions.

Architecture Overview

Our data pipeline architecture is built on three core principles: scalability, reliability, and maintainability. We leverage Apache Spark for distributed processing, Apache Kafka for real-time streaming, and cloud-native services for elastic scaling.

Key Components

  • Apache Kafka: Handles real-time data ingestion with fault tolerance
  • Apache Spark: Processes large datasets with distributed computing
  • PostgreSQL: Stores processed data with ACID compliance
  • BigQuery: Provides analytics and reporting capabilities
  • AWS/GCP: Cloud infrastructure for elastic scaling

Data Ingestion Strategy

We implemented a multi-layered ingestion strategy that handles various data sources including customer interactions, inventory updates, and third-party integrations. Each layer is designed for specific data types and processing requirements.

Real-time Processing

For time-sensitive data like inventory updates and customer orders, we use Kafka Streams to process events in real-time. This ensures that our systems reflect the most current state of our business operations.

Batch Processing

Historical data analysis and complex transformations are handled through scheduled Spark jobs that run during off-peak hours, optimizing resource utilization while maintaining data freshness.

Quality Assurance and Monitoring

Achieving 99.7% accuracy requires robust quality assurance mechanisms. We implemented comprehensive data validation, automated testing, and real-time monitoring to catch and resolve issues before they impact downstream systems.

Data Validation Framework

Our validation framework includes schema validation, data type checking, business rule validation, and anomaly detection. Each record passes through multiple validation layers before being committed to our data warehouse.

Performance Optimization

Through careful optimization of our Spark configurations, partitioning strategies, and caching mechanisms, we reduced processing time by 40% while handling increased data volumes.

Key Optimizations

  • Dynamic partitioning based on data characteristics
  • Intelligent caching of frequently accessed datasets
  • Resource allocation optimization for different job types
  • Query optimization and indexing strategies

Lessons Learned

Building data pipelines at scale taught us valuable lessons about system design, team collaboration, and operational excellence. The most important insight is that successful data engineering requires balancing technical excellence with business requirements.

Best Practices

  • Design for failure and implement comprehensive error handling
  • Monitor everything and set up meaningful alerts
  • Document data lineage and transformation logic
  • Implement gradual rollouts for pipeline changes
  • Maintain close collaboration between data engineers and stakeholders

Future Directions

We're continuously evolving our data infrastructure to handle growing data volumes and new use cases. Our roadmap includes implementing machine learning pipelines, exploring serverless architectures, and enhancing our real-time analytics capabilities.

The journey of building scalable data pipelines is ongoing, and each challenge presents an opportunity to innovate and improve. At Wayfair, we're committed to pushing the boundaries of what's possible in data engineering while maintaining the reliability and accuracy our business depends on.

Sheetal Ahuja
About the Author

Sheetal Ahuja

Software Engineer at Wayfair specializing in data engineering and scalable systems. Teaching mobile development to 250+ students at Thapar Institute. Google Cloud Professional Data Engineer and AWS Certified Cloud Practitioner with expertise in building systems that process millions of records daily.