About this project

This system consumes Google Cloud Billing budget notifications to automatically stop selected Compute Engine virtual machines when spending approaches configured limits. It operates in conservative modes by default (read-only 'plan' mode with automation disabled) and requires explicit configuration of budget names, currency, and zone allowlists. Only VMs with specific labels (budget-hardcap=true) are eligible for stopping, while protected VMs (budget-hardcap-protected=true) are always excluded. The system includes a Windows operator application for reviewing policies, previewing decisions, and inspecting audit history. It uses Firestore for event claims and action records to ensure idempotency and auditability. Important limitations: budget notifications have delays (not instantaneous), affects only Compute Engine VMs (not other GCP services), limited to one project, and requires manual setup of Cloud Billing budget connections. The documentation emphasizes this is not a replacement for provider-native spend caps or human oversight.