Software Engineer 3, Query Execution

Role overview

Join the MongoDB Server Query team to help shape a high-performance distributed open-source query engine. This group sits at the center of how data is processed in MongoDB, owning the MongoDB Query Language as well as the full lifecycle of a query: parsing, optimization, plan selection, and execution. The scope also includes geospatial search and update subsystems.

The team is growing internationally, with engineers located across North America and Europe. The organization supports both office-based and remote collaboration and works to align schedules with time zones.

This role has direct impact on transactional, time-series, and analytical workloads, and focuses on building the core of a distributed document database with flexible schema support.

Candidates should be based in Dublin to fit the hybrid working model.

Candidate profile

We are seeking software engineers with strong experience in data-intensive environments and a track record of delivering robust, production-grade systems. A solid foundation in computer science is important, especially in data structures, algorithms, and software architecture. Experience working in large codebases is also valuable.

A Bachelor’s degree in Computer Science or a related discipline, or equivalent hands-on experience, is expected. Experience with C++ and database system development is an advantage. Interest in the theory and practical implementation of database query engines is important; direct experience or an M.Sc./Ph.D. in the area is considered a plus.

What you will do

You will improve existing query engine functionality and help build new capabilities that strengthen performance, reliability, and observability. The work includes feature development, query language enhancements, diagnostics for query performance issues, and integration with other products and tools.

You will collaborate closely with fellow engineers to make coordinated changes in a large, feature-rich codebase, and you will also partner with client drivers, cloud services, enterprise tools, support, consulting, education, and marketing teams when work spans multiple products or customer-facing initiatives.

Success milestones

Within the first month, you are expected to have resolved several bugs in a minor release of the current product line. By three months, you should be contributing to a project planned for the next major release. By six months, you should be taking primary ownership of code reviews and participating in design reviews for new features. By twelve months, you should be making meaningful contributions to major new feature development.

About MongoDB

MongoDB is a data platform company focused on helping customers and teams innovate quickly in a rapidly changing market. Its cloud-native platform, MongoDB Atlas, supports globally distributed, multi-cloud deployments across AWS, Google Cloud, and Microsoft Azure. The company serves more than 67,000 customers, including 75% of the Fortune 100 as well as AI-native startups, and supports organizations modernizing legacy systems and building AI-enabled software.

The company emphasizes its Leadership Commitment as a guide for how decisions are made and how teams work together. It also invests in employee growth and wellbeing through affinity groups, fertility assistance, and a generous parental leave policy.

Accommodations and workplace support

MongoDB provides accommodations for applicants and interviewees with disabilities when needed. Candidates requiring an adjustment during the hiring process should notify their recruiter.

Additional information

Reference ID: 1273384521.