What's Happening?
Pinterest has introduced the Resource Provisioner Pipeline (RPP), a centralized Terraform execution engine designed to enhance the security of its AWS infrastructure. This system ensures least-privilege access and requires dual-control reviews, adding
strict guardrails to GitHub Actions workflows. The RPP manages numerous Terraform workspaces, which control thousands of cloud resources, including IAM policies, VPCs, load balancers, S3 buckets, and Kubernetes clusters. The pipeline activates on GitHub pull request events and operates as a central set of composite GitHub Actions, splitting a single PR into separate plan/apply runs for each affected workspace. This approach helps prevent accidental misconfigurations and malicious actions by securing the multi-repo reality without waiting for a full consolidation into a mono-repo.
Why It's Important?
The implementation of RPP is significant as it addresses the challenges of securing centralized Infrastructure as Code (IaC) pipelines, a common issue in large-scale cloud environments. By providing a single control point for infrastructure fixes, Pinterest can efficiently manage systemic issues, such as weak CI runner shells, across its infrastructure. This centralized approach allows for consistent PR-triggered checks, including static analysis and AI-assisted scanning, enhancing the overall security and reliability of Pinterest's AWS infrastructure. The RPP's focus on backend-block validation acts as a guardrail against cross-workspace state corruption, which is crucial for maintaining the integrity of cloud resources.
What's Next?
Pinterest's RPP is a private system, not open-source, but its architecture and approach can serve as a model for other organizations facing similar challenges with multi-repo Terraform setups. The company may continue to refine and expand the capabilities of RPP, potentially incorporating more advanced security features and integrations. Other organizations might adopt similar centralized IaC pipeline strategies to enhance their cloud infrastructure security, learning from Pinterest's experience and best practices.
