Detailed guide for v1 audit mode: ingest live (or synthetic) cloud inventory into Postgres, run deterministic rules over it, and produce an executive PDF + dashboard with an LLM-narrated summary.
Cloud waste is a real problem. Companies routinely overspend 20-30% on cloud infrastructure because nobody is watching the bill. CloudOracle demonstrates how to build a system that catches these issues automatically, using the same patterns that tools like AWS Trusted Advisor or Datadog Cloud Cost Management use internally.
Unlike policy engines like Cloud Custodian that focus on automated enforcement, CloudOracle is an analysis-first tool built for FinOps visibility — combining deterministic rules with LLM-generated insights to produce executive-ready reports and dashboards.
- Multi-cloud support - Switch between AWS, GCP, Azure, and synthetic data via a single env var (
CLOUDORACLE_PROVIDER) - Real AWS integration - Fetches live EC2 instances, RDS databases, EBS volumes, and Lambda functions using AWS SDK v2 with STS credential validation
- Real GCP integration - Fetches Compute Engine VMs, Cloud SQL instances, Persistent Disks, and Cloud Functions using Google Cloud Go client libraries
- Real Azure integration - Fetches Virtual Machines, Azure SQL databases, Managed Disks, and Function Apps using Azure SDK for Go
- Synthetic data generation - Realistic resource simulation across EC2, RDS, EBS, and Lambda with configurable account IDs and resource counts
- PostgreSQL persistence - Transactional bulk inserts with upsert support (
ON CONFLICT DO UPDATE) - Rule-based analysis engine - Pluggable rules architecture where each rule is a pure function
Resource -> Finding - 4 detection rules:
ec2-idle- Flags instances with <5% CPU usage running for more than 7 days (HIGH severity)rds-oversized- Identifies RDS instances with <10% CPU utilization (MEDIUM severity)ebs-orphan- Detects unattached EBS volumes with zero usage (HIGH severity)lambda-over-provisioned- Finds Lambda functions with >1GB memory and low invocation counts (LOW severity)
- Savings-ranked output - Findings are sorted by potential monthly savings (highest first)
- Service summary - Aggregated view of findings and potential savings per AWS service
- PDF report generation - Professional executive-style PDF reports with severity-coded tables, recommended actions, and annual savings projections
- LLM-powered executive summaries - Pluggable provider layer (Gemini, Claude, OpenAI) that turns raw findings into a CTO/CFO-ready narrative embedded directly into the PDF report
- Resilient LLM calls - Shared
http.RoundTripperretries 429s, 5xx, and network errors with exponential-backoff-with-full-jitter; honors theRetry-Afterheader from Anthropic/OpenAI; cancellable via the request context - Cost trend tracking - Automatic cost snapshots on every seed, with a
trendcommand that shows per-service cost changes over time with directional arrows and percentage deltas - Parallel resource fetching - Each provider fans out service calls (Compute / SQL / Disks / Functions) concurrently with
errgroup, cutting scan time on accounts with many services - Per-service timeouts - Every API call to a cloud service is wrapped in
context.WithTimeoutso a single slow region can't stall the entire scan - Structured logging (
log/slog) - Every log line carries typed attributes (provider,service,error, ...), with pluggable text or JSON output for ingestion into log aggregators - Centralized configuration - A single
config.Load()reads every env var up front and is injected into the cloud, LLM, and DB layers — no component reaches foros.Getenvon its own - Export findings to JSON or CSV - Pipe analyzer output into downstream tooling (dashboards, spreadsheets, ticket systems) via
oracle export --format=json|csv, writing to stdout or a file - Single-binary web dashboard - React + Recharts UI embedded into the Go binary via
go:embed;oracle serveboots API and dashboard on one port with no external assets required
- Go 1.25+
- Docker & Docker Compose
- (Optional) AWS CLI configured with a
cloudoracleprofile for real AWS integration (see cloud-providers.md)
Single command for the full demo (Postgres + API + embedded React dashboard):
docker compose up --build
# → open http://localhost:8080Compose brings up two services:
- postgres — PostgreSQL 16 with a healthcheck; the app only starts once it responds to
pg_isready. - app — multi-stage build of the Go binary with the React bundle embedded via
go:embed, exposed on:8080.
The app auto-applies the SQL migrations in internal/migrations/*.sql on every startup (they're idempotent — CREATE TABLE/INDEX IF NOT EXISTS), so there's no separate migration step. To populate demo data:
docker compose exec app /app/cloudoracle seed --count 120For local development without Docker you still need Postgres running somewhere; the easiest is docker compose up -d postgres and then run the Go binary on the host. Migrations run automatically whichever way you boot the app.
go run cmd/oracle/main.go seed --account acc-001 --count 100go run cmd/oracle/main.go listgo run cmd/oracle/main.go analyzego run cmd/oracle/main.go report --output cloudoracle-report.pdfThis generates a professional PDF with:
- Executive summary (total findings, monthly/annual savings projections)
- Severity breakdown (HIGH / MEDIUM / LOW)
- Color-coded findings table with cost and savings per resource
- Recommended actions for each finding
- AI-generated narrative (when an LLM provider is configured) — 3-4 paragraph executive summary written for a CTO/CFO audience, focused on financial impact, highest-priority problems, and recommended next steps
Each seed automatically creates a cost snapshot. After running seed multiple times (on different days or with different data), view how costs change:
go run cmd/oracle/main.go trend --days 30Cost Trends (last 30 days, 3 snapshots)
Service Oldest Latest Change
────────────────────────────────────────────────────────
ebs $ 100.00 $ 90.00 -10.00 (-10.0%) ↓
ec2 $ 460.00 $ 510.00 +50.00 (+10.9%) ↑
lambda $ 2.50 $ 3.10 +0.60 (+24.0%) ↑
rds $ 180.00 $ 195.00 +15.00 (+8.3%) ↑
────────────────────────────────────────────────────────
Total $ 742.50 $ 798.10 +55.60 (+7.5%) ↑
Run the analyzer and pipe its findings into another tool — a dashboard, a spreadsheet, a ticketing system. By default, the exporter writes to stdout so it composes naturally with shell pipelines; pass --output to write to a file.
# Pretty-printed JSON to stdout
go run cmd/oracle/main.go export --format=json
# CSV to a file (header row + one finding per row)
go run cmd/oracle/main.go export --format=csv --output findings.csv
# Pipe straight into jq
go run cmd/oracle/main.go export --format=json | jq '.[] | select(.Severity == "High")'The JSON output is an array of Finding objects. The CSV output has a fixed header: resource_id, service, resource_type, region, rule, severity, monthly_cost, monthly_savings, description, recommendation. Numeric fields are formatted with two decimals. Commas, quotes, and newlines in descriptions are escaped per RFC 4180 — the output is safe to open in Excel or parse with any standard CSV library.
CloudOracle ships a React + Recharts dashboard that reads the same database as the CLI. There are two workflows:
Production / demo — one binary, one command. The Go binary embeds the compiled frontend via go:embed, so after a single npm run build the whole stack (API + UI) is served on one port.
# Build the React bundle into internal/api/dist (go:embed target)
cd web
npm install # first time only
npm run build
cd ..
# Build the self-contained binary and run it
go build -o cloudoracle ./cmd/oracle
./cloudoracle serve --port 8080
# → open http://localhost:8080The binary is fully self-contained. Copy the single file (cloudoracle / cloudoracle.exe) to any machine, point it at a reachable Postgres via DB_* env vars, and the dashboard loads. No web/ directory needed at runtime.
Development — hot reload. During iteration, run the API and the Vite dev server separately so you get HMR on React changes without rebuilding Go:
# Terminal 1 — API on :8080
go run ./cmd/oracle serve --port 8080
# Terminal 2 — Vite on :5173 with /api/* proxied to :8080
cd web
npm run dev
# → open http://localhost:5173Note:
go:embedrequiresinternal/api/dist/to exist at compile time. The repo commits a.gitkeepsogo buildalways works — if you haven't runnpm run build, visiting the root route shows a "Dashboard bundle not found" page with instructions. The JSON API at/api/*works either way.
The report command will automatically call an LLM provider if any supported API key is present in the environment. No flags required — just export a key and run report again. If no key is configured, the PDF is still generated without the narrative section.
| Provider | Env variable | Default model |
|---|---|---|
| Gemini | GEMINI_API_KEY |
gemini-2.5-flash |
| Claude | ANTHROPIC_API_KEY |
claude-haiku-4-5 |
| OpenAI | OPENAI_API_KEY |
gpt-4o-mini |
# Pick one
export GEMINI_API_KEY=...
export ANTHROPIC_API_KEY=...
export OPENAI_API_KEY=...
# Force a specific provider when multiple keys are present
export LLM_PROVIDER=claude # gemini | claude | openai
go run cmd/oracle/main.go report --output cloudoracle-report.pdfAuto-detection order when LLM_PROVIDER is unset: Gemini → Claude → OpenAI. The first key found wins. LLM failures (missing key, network error, API error) are logged but never block PDF generation — the report falls back to the deterministic summary.
CloudOracle found 10 problems with potential monthly savings of $680.00
1. [HIGH] EC2 i-3592027508 (c5.xlarge) has average CPU usage of 2.8%. Active for 325 days.
Consider shutting down or terminating this instance.
Monthly Cost: $125.00 | Potential Monthly Savings: $125.00
2. [HIGH] EBS vol-fcebf509 (gp3-1000GB) is not attached to any instance. Orphaned for 60 days.
Create a backup snapshot and delete the volume.
Monthly Cost: $100.00 | Potential Monthly Savings: $100.00
3. [MEDIUM] RDS db-f7fdfc2b (db.t3.micro) has average CPU usage of 7.1%. Likely oversized.
Consider downgrading to the next smaller RDS instance tier.
Monthly Cost: $15.00 | Potential Monthly Savings: $7.50
...
Summary per service
ec2 -> 5 problems, save: $460.00/month
ebs -> 3 problems, save: $205.00/month
rds -> 2 problems, save: $15.00/month
For cloud provider setup (AWS, GCP, Azure), see cloud-providers.md. For env var reference, see configuration.md.

