Senior Backend Engineer, SSCS: Supply Chain

What you’ll do

• Design and implement backend features across the Add-On's software supply chain security surface, including policy enforcement, artifact signing and verification, provenance attestation APIs, and malicious package detection integrations, delivering secure capabilities that meet enterprise customer requirements.
• Build and improve the package policy evaluation engine, including rule compilation, request matching, enforcement decisions, and performance-sensitive execution paths tied to GitLab's Dependency Firewall infrastructure, improving accuracy, reliability, and execution performance.
• Develop artifact signing and verification workflows, including Sigstore and Cosign integrations, signing key lifecycle management, keyless signing with OpenID Connect (OIDC), and policy-based promotion gates, enabling trusted and auditable software delivery.
• Create and evolve the configuration interfaces that enterprise security teams use, including backend APIs and the GraphQL surface for expressing supply chain security requirements, improving usability and adoption for customer administrators.
• Integrate Add-On capabilities with GitLab's existing security policy framework, including policy inheritance and policy-as-code support through YAML, expanding coverage across customer security workflows.
• Collaborate with adjacent teams as malicious package intelligence is incorporated into the Add-On offering, helping deliver cohesive workflows and faster response to package risk.
• Write and maintain comprehensive RSpec and integration test coverage, and help improve test reliability across the team, increasing confidence in releases and reducing regressions.
• Review merge requests with a security-first mindset and implement solutions with substantial decision-making scope in partnership with the Staff Backend Engineer, maintaining code quality and secure engineering standards.

What you’ll bring

• Proven backend engineering experience, including production Ruby on Rails expertise, as this is the team's primary language.
• Working knowledge of Go or a clear willingness and ability to ramp up quickly in it.
• Solid API design skills, including experience with REST, GraphQL, and defining clear internal service boundaries.
• Solid PostgreSQL fundamentals, including schema design, query optimization, and indexing strategies.
• Experience with Redis for caching and distributed coordination patterns.
• A security-aware engineering mindset, with sound judgment around trust boundaries, input validation, and failure modes.
• Familiarity with software supply chain security concepts such as Supply-chain Levels for Software Artifacts (SLSA), software bill of materials (SBOM), artifact signing, or related security scanning approaches.
• Interest in complex policy, registry, or platform problems, including areas such as rules engines, package ecosystems, cryptographic signing, or DevSecOps product development.