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# Principal Test Automation Engineer

- **Company:** The Granite Group
- **Location:** Liverpool, UK
- **Experience:** Expert
- **Salary:** £70,000.0 - £80,000.0
- **Contract:** Permanent contract
- **Skills:** Reference Implementation, .NET Framework, Test Suite, Application Programming Interfaces (APIs), Agile Methodology, User Authentication, Automation of Tests, Microsoft Azure, Code Review, Databases, Continuous Integration, Microsoft SQL Server, Microsoft UI Automation, Nginx, Nunit, RabbitMQ, Azure DevOps Pipelines, Message Oriented Middleware, Service Virtualization, Test Data, TypeScript, Azure Service Bus, Performance Testing, Postman, AI Coding Agents, Backend, Git, Build Management, Integration Tests, Kubernetes, Playwright, Data Management, React Testing Library, JestJS, Docker, Web Api, Microservices
- **Published:** October 16, 2026
- **Apply:** https://www.indeed.com/viewjob?jk=6df762d7c20d7b34

## About the Role

* Senior or Principal-level experience in test automation or quality engineering, where you built the framework rather than worked within one somebody else built
 * Strong TypeScript and Playwright. Maestro or similar for mobile
 * Working proficiency in C# and .NET. You'll be writing component and integration tests against our microservices with xUnit or NUnit, and seeding test data through domain code rather than raw SQL
 * Docker and containerised test environments, including standing up infrastructure per test run with Testcontainers or equivalent
 * Service virtualisation and HTTP stubbing, using WireMock or similar, to test a service in isolation
 * Experience testing event-driven systems. Asynchronous messaging, eventual consistency, and asserting on published messages. We run RabbitMQ and Azure Service Bus through MassTransit
 * Contract testing between services with Pact or equivalent, covering message schemas as well as HTTP
 * Test data management across UI, API and database, with isolation that supports parallel runs, and synthetic or anonymised data throughout
 * SQL Server, including database-level assertions and a realistic view of how schema change affects a test suite over time
 * CI/CD pipeline and quality gate design, ideally in Azure DevOps
 * Authentication in automated tests. Token acquisition, Entra ID, and sensible handling of test credentials
 * A track record of bringing other engineers on through pairing and code review
 * Able to influence technical direction across squads without having authority over them

## Description

* Design and build the shared test harness. Ephemeral infrastructure per test run, test data seeding and teardown, third-party stubbing, database and message assertion probes. Ship it as a versioned package squads consume rather than fork
 * Define how we classify tests by what they touch, and settle what belongs in CI and what belongs in CD
 * Establish the patterns for component, contract, API, end-to-end, UI, regression and performance testing, each with a working reference implementation in our own codebase
 * Own test data. Seeding through UI automation, API calls and direct database writes, with isolation that makes parallel execution safe
 * Design the quality gates in our Azure DevOps pipelines, and own how fast and how reliably tests run, including the flaky test problem
 * Work inside squads, pairing and reviewing, so teams get self-sufficient rather than dependent on you
 * Be the escalation point when a squad is stuck on test engineering
 * Lead root cause investigation into production incidents and test flakiness, and make sure what you find is covered by regression afterwards
 * Keep the conventions and agent instruction files current so AI coding tools extend the framework consistently rather than inventing their own patterns
 * Represent quality engineering in architecture and design forums, as a peer to Tech Leads and Principal Developers
 * Own the automation metrics that matter, and use them to drive an improvement backlog rather than to report status

Our Tech Stack:

 * Backend: xUnit, WebApplicationFactory, Testcontainers for .NET, WireMock.Net, MassTransit Test Harness, Respawn, Bogus, Verify
 * Web and Mobile: Playwright with TypeScript, Maestro, Vitest, React Testing Library, Mock Service Worker
 * Testing (cross-cutting): Postman, Pact for contract testing, axe-core for accessibility, k6 and NBomber for load and performance, SonarCloud quality gates
 * Infrastructure: Azure, Docker, Kubernetes (AKS), Nginx, RabbitMQ, Azure Service Bus
 * Tooling and Practices: Azure DevOps, Git, CI/CD pipelines, Agile methodologies