Software Engineer 3

MongoDB’s Replication Team builds the infrastructure that enables high availability, fault tolerance, automatic failover, and tunable consistency. As an engineer on the team, you will design and implement distributed-systems features that protect data and keep applications available under demanding operating conditions. You will work primarily in C++ on core database code, partner with engineers across MongoDB, and help shape features that are central to major MongoDB releases. This is an opportunity to apply distributed-systems fundamentals to a widely used database while solving challenging problems in correctness, performance, and operability. We're looking to speak with candidates based in New York City for our in-office working model. What you will do Design and implement replication features based on the Raft consensus protocol Improve failover behavior, availability, correctness, and performance across the replication system Write production-quality C++ and the unit, integration, and system tests needed to demonstrate correctness Use JavaScript and Python where appropriate to extend test coverage and validate end-to-end behavior Diagnose test failures, investigate bugs, and drive issues through root-cause analysis and resolution Measure the performance impact of code changes and prevent or resolve regressions Collaborate with partner engineering teams and stakeholders on large, cross-functional initiatives Investigate distributed-systems issues raised by customers and Technical Support, communicate findings clearly, and help deliver durable fixes Participate in code reviews, design reviews, and technical discussions that improve the quality of the team’s work Interview candidates and mentor junior engineers and interns What you bring Required At least five years of experience programming, debugging, and performance-tuning distributed or highly concurrent software systems Strong systems fundamentals, including multithreaded programming, concurrency, debugging, and performance profiling Practical experience with one or more distributed-systems concepts, such as consensus protocols, replication, distributed transactions, or fault tolerance Experience working with complex production codebases and diagnosing problems that cross subsystem boundaries Strong written and verbal technical communication skills A collaborative approach and the ability to make realistic assessments of project complexity and delivery risk Preferred Professional experience developing production software in C++ Familiarity with database internals or core components of data-processing systems Experience with Raft or another consensus protocol Experience writing unit, integration, and end-to-end tests in C++, JavaScript, or Python Experience responding to customer-impacting production issues in distributed systems Experience mentoring engineers or interns and contributing to technical hiring Candidates with additional relevant experience may be considered for more senior roles. What success looks like In your first month Build a working understanding of MongoDB’s replication architecture, development workflow, and testing strategy Begin resolving scoped bugs and contributing effectively to code reviews In your first three months Contribute production C++ code to a project targeted for an upcoming MongoDB release Diagnose and resolve issues identified by testing, customers, or partner teams In your first six months Take regular ownership of code reviews and participate meaningfully in feature design reviews Independently drive scoped technical work from investigation through implementation and validation In your first twelve months Lead the development of a new feature or substantial improvement from design through delivery Help mentor new engineers and contribute to the team’s technical direction About MongoDB MongoDB is built for change, empowering our customers and our people to innovate at the speed of the m