Terraform + GitHub Actions Matrix for 200 RDS Instances, S3 Sync & Cost-Aware Slack Alerts

• 100 % backup coverage within 4 h window.
• Cost per snapshot tracked + Slack alert if >15 % spike.
• Zero manual clicks after Day-5; GitOps only.

Factory-Floor Scope I Will Build

• Terraform Factory Module
  • Matrix loop over 200 RDS ARNs ( fed from AWS Config export ).
  • Snapshot lifecycle : retain 7 days, cross-region copy to S3 Glacier.
  • Cost tag : BackupFactory=true → Cost Explorer breakdown.

• GitHub Actions Matrix Pipeline
  • Cron 04:00 UTC → strategy.matrix parallel ( max 20 jobs ).
  • Step: create snapshot → wait Available → export to S3 (parquet).
  • Cache AWS credentials with OIDC ( no long-lived keys ).

• Cost-Aware Observability
  • Lambda Cost Anomaly → compares today vs 7-day average; >15 % → Slack #cost-guardrails.
  • Grafana bar chart : snapshot count, GB, cost per env.

• Drift Guard & Manual Override
  • Terraform plan on PR → fails if manual snapshot detected.
  • Emergency workflow_dispatch button → creates on-demand snapshot with approver review.

• Compliance Evidence
  • CSV backup register : db-id, snapshot-id, start-time, cost, status.
  • Signed SHA-256 manifest stored in immutable S3 bucket.

Deliverables

• Terraform module ( reusable ) + GitHub Actions YAML.
• Cost-anomaly Lambda ( Python zip ) + Grafana dashboard JSON.
• CSV evidence + signed manifest + Cost Explorer screenshot.

Why Only a Senior Build-Engineer

• Built 3 auto-factories for FinTechs ( 500+ DBs ).
• FinOps certified → cost visibility is a feature, not an after-thought.
• 30-day cost anomaly tuning included ( shared Slack ).