Data​/ETL Tester Lead

Data / ETL Tester Lead

Transit Data Warehouse Modernization Project

Work Location:

Remote, with availability during Pacific Time business hours

Employment Type:

Contract FT

Client Environment:
Public-sector transportation/transit agency

Position Summary:

Estrada Consulting, Inc. is seeking an experienced Data / ETL Tester to support a transportation data warehouse modernization project. This role will be responsible for validating data movement, transformation logic, source-to-target mappings, data quality rules, reconciliation results, and reporting outputs across a modernized data warehouse and analytics environment. The Data / ETL Tester will work closely with the Data Architect, Data Engineers, Business Analyst / Transit Data SME, BI Developers, and Project Manager to ensure that transit-related data is accurately extracted, transformed, loaded, validated, and available for reporting, dashboards, analytics, and operational decision-making.

This role is ideal for a hands-on tester with strong SQL skills, data warehouse testing experience, ETL validation experience, and the ability to identify data quality issues across complex source systems and reporting environments.

• Develop and execute test plans, test cases, test scripts, and validation queries for data warehouse, data mart, ETL/ELT, reporting, and dashboard deliverables.
• Validate source-to-target mappings, transformation rules, business logic, calculations, aggregations, filters, joins, and derived data elements.
• Perform data reconciliation between source systems, staging tables, data warehouse tables, data marts, reports, dashboards, extracts, and downstream outputs.
• Write and execute complex SQL queries to validate data accuracy, completeness, consistency, uniqueness, timeliness, and referential integrity.
• Test ETL/ELT pipelines for data extraction, transformation, loading, scheduling, error handling, exception processing, and restart/recovery behavior.
• Validate historical data loads, incremental loads, full refreshes, data conversions, and migration results.
• Support testing of transit-related data domains such as ridership, fare data, route and stop data, schedules, trips, service planning, operational performance, customer service, and executive reporting.
• Partner with business analysts and SMEs to confirm expected business rules, KPI definitions, calculations, reporting logic, and data quality thresholds.
• Validate BI reports and dashboards to ensure displayed metrics match underlying warehouse/data mart values.
• Document defects clearly, including data examples, SQL evidence, expected results, actual results, severity, and steps to reproduce.
• Work with data engineers and developers to troubleshoot data defects, transformation issues, loading failures, duplicate records, missing records, or calculation discrepancies.
• Support user acceptance testing by preparing test data, validating report outputs, confirming business scenarios, and tracking issue resolution.
• Assist with data quality testing, including null checks, duplicate checks, domain/value checks, cross-system comparison, outlier identification, and trend validation.
• Participate in daily/weekly project meetings, defect triage sessions, requirements review, data mapping review, and implementation readiness discussions.

• Experience as a Data Tester, ETL Tester, Data Warehouse QA Analyst, BI Tester, QA Analyst, or similar role on data warehouse, business intelligence, analytics, or data modernization projects.
• Strong SQL skills, including joins, aggregations, subqueries, window functions, data comparison queries, and reconciliation queries.
• Experience validating ETL/ELT processes, source-to-target mappings, transformation logic, data loads, and data migration results.
• Experience testing data warehouses, data marts, reporting databases, dashboards, or analytics platforms.
• Ability to read and interpret data mapping documents, requirements documents, report specifications, data models, and business rules.
• Experience documenting test cases, executing test scripts, logging defects, retesting fixes, and supporting defect triage.
• Strong understanding of data quality…