Software Engineer 3

MongoDB is a data platform company empowering organizations to modernize workloads and build software for the AI era. The Software Engineer 3 will build and maintain agent tooling, evaluation systems, quality gates, and reusable automation for authoring, validating, monitoring, and improving agent skills. The role involves developing developer tools, CI workflows, observability, and safety mechanisms while collaborating with engineering, security, and product teams.

Responsibilities:

• Build and maintain agent skills and the infrastructure to validate, evaluate, publish, and maintain them
• Design evaluation datasets and workflows that compare agent behavior against a baseline and produce actionable quality signals
• Build agent metrics and observability: skill selection and routing, success and failure outcomes, tool calls, latency, and token usage
• Design safety and quality gates for agent-authored content: rule packs, static analysis, confidence thresholds, structured verdicts, and bounded suppression
• Create CLIs, libraries, and MCP integrations that other repositories adopt and that run in local development and CI
• Integrate tooling into GitHub Actions and other CI workflows, including secrets, annotations, exit codes, and artifacts
• Build code-generation quality checks, such as anti-pattern catalogs and linting for AI-generated MongoDB code
• Investigate real failures such as nondeterministic results, false positives, and unsafe generated guidance, and turn them into reusable improvements
• Collaborate with engineers, security partners, and product teams; communicate trade-offs, risks, and ownership across teams
• Ship tooling that makes agent skills or developer workflows easier to test, review, and adopt
• Improve the quality and interpretability of evaluations, not just their count
• Convert recurring manual work and fragile scripts into documented, reusable automation
• Make security, correctness, and operational trade-offs explicit in the designs you ship
• Earn adoption from partner teams through clear interfaces and reliable CI
• Own projects independently while collaborating on shared systems

Requirements:

• 2+ years of experience building production software, developer tools, internal platforms, or automation systems
• Software engineering fundamentals in API design, testing, error handling, and maintainability
• Experience building CLIs, libraries, test infrastructure, static analysis, or CI/CD workflows
• Ability to design systems that are usable by developers and reliable in automation
• Experience reasoning about correctness and safety with ambiguous input, nondeterministic output, false positives, or untrusted content
• Comfort in an evolving R&D environment where the right abstraction emerges through prototypes and feedback
• Written and verbal communication, including explaining technical trade-offs and aligning stakeholders across teams
• Experience with agentic systems, LLM applications, prompt or rubric-based evaluation, or AI-assisted development
• Experience building eval harnesses, benchmark datasets, quality metrics, LLM-as-judge workflows, or human-review tooling
• Experience with Go, Python, JavaScript/TypeScript, Java, or C#
• Experience with GitHub Actions security, secret handling, static rule engines, or policy enforcement
• Experience moving prototypes into production