Senior Software Engineer (Ruby), Security Platform: Authorization

GitLab is an intelligent orchestration platform for DevSecOps that helps organizations improve developer productivity, operational efficiency, security, compliance, and digital transformation. The Senior Software Engineer will own and evolve authorization systems across GitLab, working on Ruby on Rails policy code, fine-grained permissions, API enforcement, and migration to a next-generation authorization platform.

Responsibilities:

• Design and ship authorization changes in GitLab's Ruby on Rails monolith, where a single request can trigger hundreds of permission checks
• Own a workstream end to end. Problem definition through feature-flagged rollout, dual-run verification, and cleanup
• Build and extend fine-grained permissions for tokens and roles, and keep the permission catalog coherent as it grows
• Extend and harden authorization enforcement across GraphQL and the REST API
• Refactor long-lived policy code so both the monolith and our new authorization engine can evaluate it, without changing behavior for existing customers
• Improve the reliability, performance, and security posture of existing authorization systems, including paying down permission-model debt
• Partner with the authentication, platform, AI, and modular-service teams on interface contracts as authorization moves toward a shared service
• Drive technical decisions in writing. Design docs, architecture decision records, and code review, in a fully asynchronous organization

Requirements:

• Significant experience building and operating production Ruby on Rails applications
• Experience designing or implementing authorization systems, including role-based access control and fine-grained permissions
• A security mindset. You treat a permission bug as a security bug, and you reason about blast radius before elegance
• Comfort making careful changes to large, long-lived codebases. Incremental refactors, feature-flagged rollouts, and migrations that must not change behavior for existing users
• Working knowledge of GraphQL and API authorization patterns
• Attention to performance at scale. You understand why one uncached check matters when it runs hundreds of times per request
• Strong written communication. You are effective when most decisions happen in a document or a merge request rather than a meeting
• We welcome transferable experience from adjacent domains such as identity, policy engines, and platform security
• Preferred: hands-on PostgreSQL experience
• Helpful but not required: Rust, gRPC or Protocol Buffers, Cedar or other policy languages, Zanzibar-style authorization systems, Go, or service-oriented architecture