Apache Spark (Databricks / AWS EMR)
Distributed data processing for large-scale workloads: PySpark DataFrame API (typed transformations, Catalyst optimiser), Spark SQL (SQL over DataFrames), Spark Streaming/Structured Streaming (micro-batch streaming, exactly-once semantics), Spark MLlib (distributed ML for datasets too large for scikit-learn). Deployment: Databricks (managed auto-scaling, Delta Lake native, Unity Catalog) or AWS EMR (managed Hadoop/Spark lower cost for steady workloads).
Data Lakehouse (Delta Lake / Iceberg)
Unified data platform combining data lake scale with data warehouse ACID guarantees: Delta Lake (ACID on Parquet, time travel, schema enforcement, MERGE INTO, Z-ORDER clustering), Apache Iceberg (Netflix/Apple multi-engine, same table queryable from Spark, Flink, Trino, Athena), Apache Hudi (Uber optimised for incremental ingestion).
Apache Kafka at Scale
High-throughput event streaming: Confluent Platform (managed Schema Registry, Kafka Connect, KSQL) or AWS MSK (managed Kafka), topic design (partition count, replication factor, retention), Kafka Connect (source/sink connectors), KSQL/Kafka Streams (stream processing in Kafka), Schema Registry (Avro/Protobuf backward/forward compatibility).
Real-Time Stream Processing
Sub-second event processing pipelines: Apache Flink (stateful event time windowing, exactly-once, stateful joins, the most capable open-source stream processor), AWS Kinesis Data Analytics (managed Flink), Spark Structured Streaming (micro-batch 100ms-1s latency, simpler than Flink). Use cases: real-time fraud detection (<100ms), live analytics aggregation, IoT sensor processing.
AWS Glue + S3 Data Lake
Serverless big data processing on AWS: AWS Glue (serverless Spark ETL pay-per-DPU-second), AWS Glue Data Catalog (centralised metadata accessible from Athena, Redshift Spectrum, EMR), Amazon Athena (serverless interactive SQL on S3 pay per bytes scanned, partition pruning essential), S3 Intelligent-Tiering (automatic cost optimisation).
Data Governance & Security
Enterprise data governance for large-scale data platforms: Unity Catalog (Databricks column-level access control, data lineage, PII tagging and masking, row-level security), Apache Ranger (policy-based access control), data masking (PII columns for non-production access), data lineage (OpenLineage + Marquez trace from raw source to BI dashboard, essential for GDPR).