Data Quality Tester - SQL, data testing, ETL validation, reporting quality assurance, CI/CD testing

Role - Data Quality Tester - SQL, data testing, ETL validation, reporting quality assurance, CI/CD testing, and data governance experience.

Up to £300 per day
Location - London Office - up to 2 days a week

We're looking for a Data Quality Tester to play a critical role in ensuring the accuracy, reliability, and integrity of data across a growing data platform. This position will help accelerate delivery timelines while maintaining high-quality standards across reporting and analytics.

This is an excellent opportunity for someone with strong SQL, data testing, ETL validation, reporting quality assurance, CI/CD testing, and data governance experience who enjoys building quality processes from the ground up.

Key requirements:

Own and enhance data quality frameworks across data ingestion, transformation, and reporting layers.

Define, implement, and maintain automated data quality rules, determining appropriate failure behaviours based on business impact.

Develop and maintain automated regression testing for business-critical reports to identify defects before deployment.

Build contract tests that validate schemas and pipeline outputs, preventing upstream changes from breaking downstream reporting.

Create and manage representative test datasets covering complex scenarios, including null values, CDC sequences, and multi-entity data.

Implement automated data assertions and quality gates within CI/CD pipelines to prevent inaccurate or incomplete data reaching production.

Define and maintain report validation baselines, including row counts, key metrics, and variance thresholds.

Investigate and reproduce data defects reported by users, converting incidents into reusable automated regression tests.

Collaborate closely with developers, analysts, and business stakeholders to translate business requirements into measurable and automated data quality controls.

Review transformation logic, SQL changes, and pull requests to ensure all critical business logic is adequately tested before release.