API Test Infrastructure Engineer

About this role

ABOUT THE ROLE We are looking for an API Test Infrastructure Engineer to join our engineering team. This is a platform-focused role sitting at the intersection of software engineering, quality, and DevOps. The engineer will be responsible for building and owning the foundational infrastructure that enables our engineering teams to test APIs at scale, with confidence and speed. You will not be the sole author of all tests. Instead, your primary mission is to build the platform, tooling, and patterns that make it easy for every engineer to write high-quality API tests. You will also own a set of integrations with external tools and services, continuously validating that those integrations behave correctly through automated API-level testing. CORE RESPONSIBILITIES TEST INFRASTRUCTURE & PLATFORM - Design, build, and maintain a robust, automated API testing infrastructure that can be spun up reproducible across local, CI, and production-mirror environments. - Develop and maintain a shared library of reusable test utilities, fixtures, helpers, and patterns for use across engineering teams. - Own the containerization strategy for test environments using Docker (and related tooling), ensuring tests run consistently and reliably regardless of where they execute. - Integrate the testing infrastructure into existing CI/CD pipelines, including test reporting, alerting, and failure triage workflows. - Continuously evaluate and introduce new tools, frameworks, and practices that improve the reliability, speed, or coverage of the infrastructure. EXTERNAL TOOL INTEGRATIONS & CONTINUOUS VALIDATION - Build and maintain a suite of automated integration tests that validate the behavior of third-party and external API-based tools the organisation depends on. - Design monitoring and alerting strategies that detect regressions or unexpected changes in external API behavior as early as possible. - Collaborate with internal teams to understand integration requirements and translate them into automated, continuously-running test scenarios. REQUIRED SKILLS & EXPERIENCE - Python scripting: strong scripting ability with experience writing clean, maintainable, production-quality Python code used in test tooling and automation frameworks. - API standards: solid understanding of REST, GraphQL, and related API conventions including request/response life-cycles, pagination, error handling, and versioning. - API security: practical knowledge of API-level security concepts including authentication (OAuth 2.0, API keys, JWT), authorization patterns, and how to validate security controls through tests. - Automated testing: experience designing, building, and maintaining automated test suites; familiarity with frameworks such as pytest, and an understanding of test architecture (unit, integration, contract, end-to-end). - Containerization: hands-on experience with Docker to create reliable, reproducible test environments; experience with Docker Compose or similar tooling for orchestrating multi-service test setups. - CI/CD integration: experience integrating automated tests into CI/CD pipelines (e.g. GitHub Actions, GitLab CI, Jenkins) including test reporting and gating strategies. WHAT A TYPICAL DAY LOOKS LIKE - Improving or extending the core testing infrastructure; making it faster, more reliable, or easier for other engineers to use. - Reviewing the landscape of available tooling and evaluating whether something new could meaningfully improve the platform. - Building or extending an integration test for an external API-based tool; writing the scaffolding, the assertions, and connecting it to the reporting pipeline. - Pairing with a product engineer to help them write a new API test using shared infrastructure, or reviewing a test they've written for quality and consistency. - Investigating a test failure in CI. Diagnosing whether it represents a real regression, an environment issue, or a flaky test, and resolving accordingly. - Contributing to documentation, playbooks, and internal guides that help engineers self-serve on the testing platform. HOW SUCCESS IS MEASURED - Platform adoption: engineers across teams are able to write and run API tests using the shared infrastructure with minimal friction. - Infrastructure reliability: test environments spin up fully automated and consistently; flakiness rates are low and trending downward. - Coverage of external integrations: critical third-party API integrations are covered by continuously-running automated tests with clear alerting on failure. - CI/CD integration quality: test results are visible, actionable, and correctly gate deployments across the pipeline. - Time to onboard new tests: the effort required to add a new test to the platform is low and well-documented. NICE TO HAVE - Experience with API contract testing. - Familiarity with observability tooling (e.g. Grafana, Datadog) for monitoring test pipelines and external service health. - Exposure to Kubernetes or other container orchestration platforms. - Experience contributing to or maintaining internal developer platforms or tooling. - Background in a polyglot environment. Exposure to languages beyond Python (e.g. TypeScript/JavaScript) is a plus. WHAT WE OFFER - A high-impact role with clear ownership of a critical engineering platform. - Close collaboration with engineering teams across the organisation. - The opportunity to shape how quality and testing are practiced at scale. - A culture that values engineering craft, automation, and continuous improvement.