Data QA Engineer: End-to-End Data Quality

Sagacity; City Of London; On-site; GBP 55,000 - 75,000; Full time

Job summary

Sagacity is seeking a QA/Data Test Engineer to bridge data analysis and quality assurance. You will design and execute tests across data pipelines, data warehouses and lakehouse platforms, reconciling data from source to target and ensuring high data quality for clients in financial services, retail, and more.

You will collaborate with Data Engineers, UAT teams and client stakeholders, turning mappings into test cases, and logging clear defects for rapid fixes.

Qualifications

• 2+ years in data testing, data quality, data analysis or QA with data focus.
• Client-facing or consulting experience: presenting findings to non-technical audiences, managing expectations and building relationships
• Working with development or data engineering teams in an agile or iterative delivery environment
• Strong SQL: joins, CTEs, aggregations and window functions are essential
• Data pipeline testing across ETL/ELT and data warehouse or lakehouse environments
• Data quality concepts: completeness, accuracy, duplicates, schema, transformation logic

Responsibilities

• Write and run SQL to check, profile and reconcile data across source systems, staging, data warehouse and lakehouse layers
• Test ETL/ELT pipelines end to end, validate transformation logic and business rules
• Carry out data quality checks covering completeness, accuracy, duplicates, schema and row volumes
• Perform source-to-target reconciliation and migration parity checks
• Write, run and maintain test plans and test cases from mappings, specs and acceptance criteria
• Investigate failures and anomalies and log clear defects for developers
• Work with clients and UAT teams to explain testing approach and manage expectations
• Collaborate with Data Engineers to validate fixes before UAT/production
• Manage QA work items in ClickUp and improve SPHERE tooling
• Use AI-assisted tools to speed up test authoring, investigation and documentation

Skills

Strong SQL

Data pipeline testing

Data quality

Reconciliation & test design

Analytical mindset

Git basics

Tools

Python/PySpark

Databricks Unity Catalog

Azure/AWS data services

dbt/Great Expectations/Soda

YAML configurations

AI-assisted engineering tools

Job description

Sagacity is seeking a QA/Data Test Engineer to bridge data analysis and quality assurance. You will design and execute tests across data pipelines, data warehouses and lakehouse platforms, reconciling data from source to target and ensuring high data quality for clients in financial services, retail, and more.

You will collaborate with Data Engineers, UAT teams and client stakeholders, turning mappings into test cases, and logging clear defects for rapid fixes.