Career Guide
Data engineers build the systems that make data usable. Pipelines, warehouses, quality checks, and the infrastructure that analysts and scientists depend on every day. Compensation is strong and growing, with senior roles well into six figures.
22.6% of DE job filings are in Texas, making it the largest market by volume. California follows at 13.5%, Washington at 9.6%.
Code that moves data from point A to point B on a schedule. Pull from APIs, databases, flat files, or event streams. Transform it along the way. Load it into a warehouse or lake.
The central store where analysts and scientists query data. You design the schema, write the transformations, and keep tables fresh. Star schemas, slowly changing dimensions, incremental loads.
The infrastructure layer: orchestration, monitoring, alerting, access controls, and documentation. You make sure data is available, correct, and discoverable.
Data tests, freshness checks, schema validation, row count assertions. When a pipeline breaks at 3 AM, the alert should tell you exactly what failed and why.
| Data Engineer | Data Scientist | Data Analyst | |
|---|---|---|---|
| Primary output | Pipelines, schemas, infrastructure | Models, experiments, predictions | Reports, dashboards, recommendations |
| Core language | SQL + Python | Python + R | SQL + BI tools |
| SQL depth | Advanced (optimization, DDL, CTEs) | Intermediate | Intermediate to advanced |
| Day-to-day | Building and maintaining systems | Training models, running experiments | Answering business questions with data |
| Interview focus | SQL, Python, data modeling | Statistics, ML, coding | SQL, analytics, business cases |
Morning. Check pipeline monitoring dashboards. Investigate any overnight failures. Fix or restart stuck jobs.
Mid-morning. Write or review a data model change. Discuss schema design with the analytics team. Write SQL transformations.
Afternoon. Build a new pipeline for a data source the product team needs. Write tests. Deploy to staging.
Late afternoon. Code review a teammate's PR. Update documentation. Plan tomorrow's work.
Most data engineering interview loops include 3 to 5 rounds. Here is what to expect.
Nearly 7 out of 10 DE interviews include a SQL round. Window functions, CTEs, subqueries, JOINs, aggregation. You type into a shared editor and your output is checked against expected results.
Data manipulation, string processing, file parsing. Simpler than a software engineering coding round, but you still need clean, working code in 30-45 minutes.
Design a schema on a whiteboard. Normalization, trade-offs, SCD types. Star schema appears in 4.7% of interviews. System design (batch vs streaming, pipeline architecture) shows up in only 2.8% of rounds.
Past projects, debugging stories, team collaboration. Prepare 3-4 stories about data quality issues you solved or pipelines you built.
10th-25th Percentile
Median well above six figures
75th-90th percentile significantly above median
Based on verified federal labor certification filings. For the full breakdown by percentile and geography, see our salary guide.
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