Senior SDET Engineer, Query

The MongoDB Query Team is hiring Software Engineers who want to join us in building a state-of-the-art distributed query system. We are responsible for the MongoDB Query Language and the lifecycle of each query, from parsing to optimization to plan selection; our engineers work on maintaining and improving our optimization and execution frameworks and building new query language features to help power our customers' critical workloads. Throughout all our work, our highest priority is always ensuring that customer queries are answered correctly. The successful applicant will be responsible for helping us to maintain the highest standards of quality through rigorous testing and automation strategies.

This role can be based out of our Dublin office, or remotely in the Ireland region.

Candidate Profile

• Minimum 5 years of experience in QA automation or software development with a focus on test automation
• Ability to work in highly ambiguous environments
• Experience with testing multi-tiered backend systems
• Design, implement, and maintain custom test frameworks to validate functionality, reliability, and performance across multi-tiered backend or distributed systems
• Proficiency in writing and maintaining test automation frameworks for large codebases
• Solid foundation in computer science, with knowledge of data structures, algorithms, and software design/architecture
• Experience in developing performance test plans and monitoring frameworks
• High-level proficiency in writing and optimizing complex database queries, including multi-table joins, subqueries, aggregations, and filtering logic, as well as an understanding of how the database engine executes and processes those queries
• Significant hands-on experience working with relational and/or NoSQL databases in a professional setting
• Ability to independently diagnose and resolve query performance issues, including interpreting and acting on execution plans to identify bottlenecks
• Experience in distributed query processing engines performance testing is a strong plus
• B.Sc. in Computer Science or related field, or equivalent practical experience. Advanced degrees of experience in database query engines is a plus
• Previous experience in testing database query engines or compilers is a strong plus

Position Expectations

• Design, develop, and maintain correctness and performance automated tests and testing frameworks for the MongoDB query engine
• Collaborate closely with peers to understand new features and functionalities, ensuring testability and coverage for automating tests of both happy-path and edge-case scenarios
• Identify, isolate, and document bugs and issues within the database query system. Work with developers to ensure issues are resolved
• Enhance and extend the automation framework to improve test coverage, execution time, and tooling for diagnostics and performance testing
• Review and approve testing plans drawn up in the design phase of Query team projects. At the end of the project, certify that it has met its commitments regarding test coverage
• Provide feedback in code reviews, focusing on the robustness and reliability of code changes from a testing perspective

Success Measures

• Within three months, you have gained an understanding of MongoDB's MQL syntax and its semantics, as well as the behavior of our unique query engine and its interaction with other server systems (storage/indexes, sharding, etc). You are able to contribute effectively for testing improvements in correctness and performance testing
• By six months, you have established yourself as a reviewer for automated tests, independently leading the testing efforts for complex functionalities, and demonstrating improvements in test efficiency and coverage. You have contributed to increasing the automated test coverage for upcoming releases
• After twelve months, you are a solid contributor to testing strategy for new features, supporting new team members in best practices for test automation, performance testing and quality assurance

About MongoDB

MongoDB is built for change, empowering our customers and our people to innovate at the speed of the market. We have redefined the database for the AI era, enabling innovators to create, transform, and disrupt industries with software. MongoDB’s unified database platform, the most widely available, globally