Senior Backend Engineer (RoR), Software Supply Chain Security: Authorization

An overview of this role

As a Senior Backend Engineer on the Authorization team at GitLab, you'll build and evolve the core systems that decide who can access what across the entire GitLab platform, directly impacting millions of users from startups to large enterprises. You'll architect and implement our next-generation authorization infrastructure, including policy-as-code approaches, fine-grained permissions, and performance optimizations at massive scale, enabling GitLab's move toward zero-trust architecture while keeping authorization fast, secure, and correct. You'll work closely with Security, Database, Platform, and authentication-focused teams to design and ship authorization capabilities that span GitLab's various deployment models and multi-tenant environments.

Some examples of our projects:

• Implementing fine-grained permissions for Job Tokens, Personal Access Tokens, and the GitLab Duo agent platform
• Collaborating on Auth stack initiatives that evolve how authorization works across GitLab

What you’ll do

• Implement fine-grained permission systems for Job Tokens, Personal Access Tokens, the GitLab Duo Agent Platform, and other authentication mechanisms across the GitLab platform.
• Collaborate with Security, Authentication, Database, and Platform teams on authorization stack initiatives, aligning designs and implementation plans.
• Solve complex performance challenges in authorization, including query optimization, caching strategies, and database decomposition, with a focus on PostgreSQL.
• Design and evolve authorization systems that work across multiple deployment models and multi-tenant architectures while maintaining security and reliability.
• Drive improvements to authorization security, maintainability, and developer experience through code review, documentation, and technical leadership.
• Contribute to architectural decisions for authorization features with a long-term strategic view, balancing immediate needs with future scalability.
• Mentor and support other engineers in authorization patterns, policy-based access control, and secure coding practices in a fully remote, asynchronous environment.
• Contribute to frontend vue.js code, as needed

What you’ll bring

• Professional experience building and maintaining production applications with Ruby on Rails or similar backend frameworks.
• Strong understanding of authorization models, including role-based access control, attribute-based access control, and fine-grained permission patterns.
• Experience designing and optimizing high-scale backend systems, including PostgreSQL performance tuning, query optimization, and effective caching strategies.
• Familiarity with or interest in policy-based authorization systems and modern policy languages such as Cedar or Rego.
• Understanding of core security principles, including threat modeling, least-privilege access, and zero-trust architectures.
• Experience working with distributed systems and service-to-service communication in a cloud or multi-tenant environment.
• Demonstrated ability to own complex technical initiatives from design through production deployment in an asynchronous, remote setting.
• Strong collaboration and communication skills, with openness to learning and applying transferable skills from adjacent domains or technologies.

About the team

We on the Authorization team at GitLab design, build, and maintain the permission systems that control access across the GitLab platform, ensuring they are secure, scalable, and flexible for customers of all sizes. We lead the ongoing evolution of our authorization architecture, with a focus on modern policy-as-code approaches, fine-grained access control, and support for initiatives like the evolving Auth stack. We collaborate asynchronously across time zones and partner closely with Authentication, Product Security, Database, and Security teams to align on identity, data modeling, and threat modeling needs while iterating safely on core platform capabilities.