# Use Case and Detection Engineering Lifecycle
One-sentence definition: A repeatable path from hypothesis to reliable alert with continuous tuning.
## Key Facts
- Steps: hypothesis → data mapping → rule/build → test → deploy → tune → measure.
- Map to ATT&CK techniques and required telemetry.
- Add context/enrichment (asset criticality, user risk) for fidelity.
- Measure precision/recall; retire low-value rules.
- **Verify:** check official (ISC)² CBK and current exam outline.
## Exam Relevance
- Choose lifecycle to justify alert quality and maintenance.
**Mnemonic:** “**Think → Build → Prove → Improve**.”
## Mini Scenario
Q: Alert noisy on service accounts—improvement?
A: Exempt patterns or add conditions (interactive logons only).
## Revision Checklist
- List lifecycle steps.
- Telemetry mapping.
- Metric to track.
## Related
[[Logging Strategy and SIEM Use Cases]] · [[MITRE ATT&CK Mapping for Testing]] · [[Playbooks and SOAR Automation]] · [[Threat Hunting Program Basics]] · [[Operational Metrics and KPIs (MTTD MTTR Coverage)]] · [[Domain 7 - Index]]