Google Cloud Platform Cloud Functions Firestore Cloud Storage Pub/Sub BigQuery Authentication Anti-Patterns | Anti-Pattern | Fix | |--------------|-----| | Service account key files in repo | Use Application Default Credentials | | Not using composite indexes (Firestore) | Define indexes for multi-field queries | | Synchronous Pub/Sub publish | Batch messages, use | | Full table scans in BigQuery | Use partitioned/clustered tables | | No IAM least privilege | Grant minimum required roles per service | Production Checklist - [ ] Application Default Credentials (no key files) - [ ] IAM roles wi…