Backend Engineer, AI Engineering: Duo Chat

GitLab is the intelligent orchestration platform for DevSecOps. GitLab enables organizations to increase developer productivity, improve operational efficiency, reduce security and compliance risk, and accelerate digital transformation. More than 50 million registered users and more than 50% of the Fortune 100* trust GitLab to ship better, more secure software faster. The same principles built into our products are reflected in how our team works: we embrace AI as a core productivity multiplier, with all team members expected to incorporate AI into their daily workflows to drive efficiency, innovation, and impact. GitLab is where careers accelerate, innovation flourishes, and every voice is valued. Our high-performance culture is driven by our values and continuous knowledge exchange, enabling our team members to reach their full potential while collaborating with industry leaders to solve complex problems. Co-create the future with us as we build technology that transforms how the world develops software. * Fortune 500® is a registered trademark of Fortune Media IP Limited, used under license. Claim based on GitLab data. Fortune 100 refers to the top 20% ranked companies in the 2025 Fortune 500 list, published in June 2025. Fortune and Fortune Media IP Limited are not affiliated with, and do not endorse products or services of GitLab. An overview of this role As a Backend Engineer on the Chat Engine team, you'll build the engine behind GitLab Duo Chat, the conversational AI experience for GitLab. You'll work primarily in Python to build and maintain our agentic runtime: the Flow Registry, LangGraph flows, and the Duo Workflow Service. You'll also work in the GitLab Rails monolith, where Chat connects with the product. You'll own scoped parts of the system, ship small features and improvements with minimal guidance, and collaborate with the team on larger projects. You'll work alongside senior and staff engineers who will partner with you on design and support your growth. What you’ll do Develop secure, well-tested, and performant features and improvements for GitLab Duo Chat. Implement and extend agentic flows in Python using LangGraph, registered through the Flow Registry and served by the Duo Workflow Service. Integrate Chat capabilities with the GitLab Rails monolith, including its GraphQL application programming interface (API). Write maintainable code that meets our internal standards for a high-scale environment, including tests with every merge request. Review code within our Code Review Guidelines and respond promptly to contributions from people who don't work for GitLab. Identify technical debt and propose and implement solutions that improve the team's efficiency. Collaborate with Product Management, User Experience, and Frontend team members to improve product quality, security, and performance. Participate in Tier 2 or Tier 3 weekday, weekend, and occasional night on-call rotations to help troubleshoot product operations, security operations, and urgent engineering issues. What you’ll bring Professional experience with Python, including building and testing production services. Working proficiency with Ruby on Rails, or a willingness to learn it, since a meaningful part of Chat lives in the GitLab monolith. Exposure to, or strong interest in, building on top of large language models, including prompting, tool or function calling, evaluation, and the failure modes of non-deterministic systems. Experience designing and building APIs, including diagnosing and optimizing performance issues, and comfort working with well-documented third-party services. A security-minded development approach that applies secure coding guidelines early in the development process. Clear and concise written communication about technical problems and iterative solutions, which is essential in a remote, largely asynchronous environment. Manage work independently, organize priorities, and ask for help when an issue is taking longer than exp