senior-data-engineer

# Senior Data Engineer Production-grade data engineering skill for building scalable, reliable data systems. ## Table of Contents 1. [Trigger Phrases](#trigger-phrases) 2. [Quick Start](#quick-start) 3. [Workflows](#workflows) - [Building a Batch ETL Pipeline](#workflow-1-building-a-batch-etl-pipeline) - [Implementing Real-Time Streaming](#workflow-2-implementing-real-time-streaming) - [Data Quality Framework Setup](#workflow-3-data-quality-framework-setup) 4. [Architecture Decision Framework](#architecture-decision-framework) 5. [Tech Stack](#tech-stack) 6. [Reference Documentation](#reference-documentation) 7. [Troubleshooting](#troubleshooting) --- ## Trigger Phrases Activate this skill when you see: **Pipeline Design:** - "Design a data pipeline for..." - "Build an ETL/ELT process..." - "How should I ingest data from..." - "Set up data extraction from..." **Architecture:** - "Should I use batch or streaming?" - "Lambda vs Kappa architecture" - "How to handle late-arriving data" - "Design a data lakehouse" **Data Modeling:** - "Create a dimensional model..." - "Star schema vs snowflake" - "Implement slowly changing dimensions" - "Design a data vault" **Data Quality:** - "Add data validation to..." - "Set up data quality checks" - "Monitor data freshness" - "Implement data contracts" **Performance:** - "Optimize this Spark job" - "Query is running slow" - "Reduce pipeline execution time" - "Tune Airflow DAG" --- ## Quick Start ### Core Tools ```bash # Generate pipeline orchestration config python scripts/pipeline_orchestrator.py generate \ --type airflow \ --source postgres \ --destination snowflake \ --schedule "0 5 * * *" # Validate data quality python scripts/data_quality_validator.py validate \ --input data/sales.parquet \ --schema schemas/sales.json \ --checks freshness,completeness,uniqueness # Optimize ETL performance python scripts/etl_performance_optimizer.py analyze \ --query queries/daily_aggregation.sql \ --engine spark \ --recommend ``` --- ## Workflows → See references/workflows.md for details ## Architecture Decision Framework Use this framework to choose the right approach for your data pipeline. ### Batch vs Streaming | Criteria | Batch | Streaming | |----------|-------|-----------| | **Latency requirement** | Hours to days | Seconds to minutes | | **Data volume** | Large historical datasets | Continuous event streams | | **Processing complexity** | Complex transformations, ML | Simple aggregations, filtering | | **Cost sensitivity** | More cost-effective | Higher infrastructure cost | | **Error handling** | Easier to reprocess | Requires careful design | **Decision Tree:** ``` Is real-time insight required? ├── Yes → Use streaming │ └── Is exactly-once semantics needed? │ ├── Yes → Kafka + Flink/Spark Structured Streaming │ └── No → Kafka + consumer groups └── No → Use batch └── Is data volume > 1TB daily? ├── Yes → Spark/Databricks └── No → dbt + warehouse compute ``` ### Lambda vs Kappa Architecture | Aspect | Lambda | Kappa | |--------|--------|-------| | **Complexity** | Two codebases (batch + stream) | Single codebase | | **Maintenance** | Higher (sync batch/stream logic) | Lower | | **Reprocessing** | Native batch layer | Replay from source | | **Use case** | ML training + real-time serving | Pure event-driven | **When to choose Lambda:** - Need to train ML models on historical data - Complex batch transformations not feasible in streaming - Existing batch infrastructure **When to choose Kappa:** - Event-sourced architecture - All processing can be expressed as stream operations - Starting fresh without legacy systems ### Data Warehouse vs Data Lakehouse | Feature | Warehouse (Snowflake/BigQuery) | Lakehouse (Delta/Iceberg) | |---------|-------------------------------|---------------------------| | **Best for** | BI, SQL analytics | ML, unstructured data | | **Storage cost** | Higher (proprietary format) | Lower (open formats) | | **Flexibility** | Schema-on-write | Schema-on-read | | **Performance** | Excellent for SQL | Good, improving | | **Ecosystem** | Mature BI tools | Growing ML tooling | --- ## Tech Stack | Category | Technologies | |----------|--------------| | **Languages** | Python, SQL, Scala | | **Orchestration** | Airflow, Prefect, Dagster | | **Transformation** | dbt, Spark, Flink | | **Streaming** | Kafka, Kinesis, Pub/Sub | | **Storage** | S3, GCS, Delta Lake, Iceberg | | **Warehouses** | Snowflake, BigQuery, Redshift, Databricks | | **Quality** | Great Expectations, dbt tests, Monte Carlo | | **Monitoring** | Prometheus, Grafana, Datadog | --- ## Reference Documentation ### 1. Data Pipeline Architecture See `references/data_pipeline_architecture.md` for: - Lambda vs Kappa architecture patterns - Batch processing with Spark and Airflow - Stream processing with Kafka and Flink - Exactly-once semantics implementation - Error handling and dead letter queues ### 2. Data Modeling Patterns See `references/data_modeling_patterns.md` for: - Dimensional modeling (Star/Snowflake) - Slowly Changing Dimensions (SCD Types 1-6) - Data Vault modeling - dbt best practices - Partitioning and clustering ### 3. DataOps Best Practices See `references/dataops_best_practices.md` for: - Data testing frameworks - Data contracts and schema validation - CI/CD for data pipelines - Observability and lineage - Incident response --- ## Troubleshooting → See references/troubleshooting.md for details --- ## Why This Skill Exists Implement — Data engineering skill for building scalable data pipelines, ETL/ELT systems, and data infrastructure. Expertise in Python, SQL, Spark, Airflow, dbt, Kafka, and modern data stack. <!-- SR_40: auto-generated from frontmatter `purpose`/`description` (OPP-Phase3). Expand with domain-specific rationale. --> ## When to Use Use this skill when the task requires senior data engineer capabilities. <!-- SR_40: auto-generated from frontmatter `when`/`description` (OPP-Phase3). --> ## What If Fails If this skill fails to produce the expected output: (1) verify input completeness, (2) retry with more specific context, (3) fall back to the parent workflow without this skill. <!-- SR_40: auto-generated from frontmatter `what_if_fails` (OPP-Phase3). -->