2nd/10_Wiki/Topics/DevOps_and_Security/Engineering Metrics (DORA).md

---
id: wiki-2026-0508-engineering-metrics-dora
title: Engineering Metrics (DORA)
category: 10_Wiki/Topics
status: verified
canonical_id: self
aliases: [DORA, DORA Metrics, Four Keys, DevOps Research and Assessment]
duplicate_of: none
source_trust_level: A
confidence_score: 0.9
verification_status: applied
tags: [devops, metrics, dora, sre, engineering]
raw_sources: []
last_reinforced: 2026-05-10
github_commit: pending
tech_stack:
  language: yaml
  framework: github-actions
---

# Engineering Metrics (DORA)

## 매 한 줄
> **"매 deployment frequency, lead time, change fail rate, MTTR — 4 metric 으로 매 engineering org 의 health 측정"**. 매 2014 Google DORA team 의 launch, 매 2021 SPACE framework 보완, 매 2026 GitHub/GitLab/Datadog 의 native dashboard 의 default.

## 매 핵심

### 매 Four Keys
- **Deployment Frequency (DF)**: 매 production deploy 의 빈도. Elite = on-demand (multiple/day).
- **Lead Time for Changes (LT)**: 매 commit → production. Elite = < 1 day.
- **Change Failure Rate (CFR)**: 매 deploy 의 incident 유발 비율. Elite = 0–15%.
- **Mean Time to Recovery (MTTR)**: 매 incident → restore. Elite = < 1 hour.

### 매 Performance tier
- **Elite**: DF on-demand · LT < 1day · CFR 0–15% · MTTR < 1h.
- **High**: DF weekly–daily · LT 1day–1wk · CFR 16–30% · MTTR < 1day.
- **Medium**: DF monthly · LT 1wk–1mo · CFR 16–30% · MTTR 1day–1wk.
- **Low**: DF < monthly · LT > 1mo.

### 매 응용
1. Sprint retro 매 주 review.
2. Quarterly engineering OKR target.
3. Hiring/promo signal (team-level, 매 individual 아님).

## 💻 패턴

### GitHub Actions deployment frequency
```yaml
# .github/workflows/deploy.yml
name: deploy
on:
  push:
    branches: [main]
jobs:
  deploy:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - run: ./deploy.sh
      - name: Emit DORA event
        run: |
          curl -X POST https://api.dora-collector.internal/events \
            -H "Authorization: Bearer ${{ secrets.DORA_TOKEN }}" \
            -d '{"type":"deploy","sha":"${{ github.sha }}","ts":"'$(date -u +%FT%TZ)'"}'
```

### Lead time calculation (SQL)
```sql
-- commits joined with deploys
SELECT
  PERCENTILE_CONT(0.5) WITHIN GROUP (ORDER BY EXTRACT(EPOCH FROM (deploy_ts - commit_ts))/3600) AS p50_hours,
  PERCENTILE_CONT(0.95) WITHIN GROUP (ORDER BY EXTRACT(EPOCH FROM (deploy_ts - commit_ts))/3600) AS p95_hours
FROM dora_events
WHERE deploy_ts >= NOW() - INTERVAL '30 days';
```

### Change failure rate from incidents
```python
# rolling 30d CFR
def cfr(deploys: list[dict], incidents: list[dict]) -> float:
    bad_deploys = {i["deploy_sha"] for i in incidents if i["caused_by_deploy"]}
    return len(bad_deploys) / max(len(deploys), 1)
```

### MTTR via PagerDuty
```python
import httpx, statistics
def mttr(api_key: str, since: str) -> float:
    r = httpx.get("https://api.pagerduty.com/incidents",
                  headers={"Authorization": f"Token token={api_key}"},
                  params={"since": since, "statuses[]": "resolved"})
    durations = [(i["resolved_at_ts"] - i["created_at_ts"]) for i in r.json()["incidents"]]
    return statistics.median(durations) / 60  # minutes
```

### Four Keys dashboard (Datadog)
```yaml
# datadog-dora.yaml
widgets:
  - title: Deployment Frequency
    query: "sum:dora.deploy{*}.as_count().rollup(sum, 86400)"
  - title: Lead Time p50
    query: "p50:dora.lead_time_seconds{*}"
  - title: CFR
    query: "sum:dora.deploy_failed{*} / sum:dora.deploy{*}"
  - title: MTTR p50
    query: "p50:dora.incident_resolve_seconds{*}"
```

### Trunk-based config (lead time 단축)
```yaml
# .github/branch-protection.yml
required_status_checks:
  strict: true
  contexts: [ci/test, ci/lint]
required_pull_request_reviews:
  required_approving_review_count: 1
  dismiss_stale_reviews: true
restrictions: null  # 매 직접 push 매 X — PR-only
```

## 매 결정 기준
| 상황 | Approach |
|---|---|
| Startup (<20 eng) | DF + LT 매 우선, MTTR 매 secondary |
| Regulated industry | CFR 매 primary (release safety) |
| Platform team | All 4, 매 weekly review |
| Individual perf review | 매 X — team metric only |

**기본값**: 매 four-keys-platform (Google open source) self-host + Grafana.

## 🔗 Graph
- 부모: [[DevOps]] · [[Site Reliability Engineering]]
- 응용: [[Continuous Delivery]] · [[Continuous Integration]]

## 🤖 LLM 활용
**언제**: deploy log → metric extraction, incident root-cause 분류 (deploy 유발 여부).
**언제 X**: 매 individual contributor scoring 매 X — DORA 매 team-level only.

## ❌ 안티패턴
- **Goodharting**: DF 만 chase 하고 quality 무시 → CFR 폭증.
- **Individual scoring**: developer 별 LT 측정 → gaming (small commits 만).
- **Vanity rollups**: org-wide average — 팀 distribution 의 hide.
- **No CFR**: deploy 만 count, failure track X → false elite signal.

## 🧪 검증 / 중복
- Verified (DORA "State of DevOps" 2014–2024 reports, Google Cloud 공식).
- 신뢰도 A.

## 🕓 Changelog
| 날짜 | 변경 |
|---|---|
| 2026-05-08 | Phase 1 |
| 2026-05-10 | Manual cleanup — DORA four-keys 정의 + dashboard pattern |