nw-platform-engineering-foundations

# Platform Engineering Foundations ## Continuous Delivery (Humble and Farley) Key principles: Build quality in | Work in small batches | Automate almost everything | Pursue continuous improvement | Everyone is responsible (shared ownership). Pipeline progression: Commit -> Acceptance -> Capacity -> Production stages. For detailed stage definitions and quality gates, see `cicd-and-deployment` skill. ## Site Reliability Engineering (Google -- Beyer et al.) Key principles: SLOs over SLAs (internal targets stricter than external) | Error budgets (balance reliability and velocity) | Toil elimination (automate repetitive manual work) | Embrace risk (calculate risk, do not eliminate it). Observability: Four Golden Signals (latency, traffic, errors, saturation) | SLI -> SLO -> Error Budget -> Alerting chain | Dashboards for investigation, not monitoring. ## Accelerate (Forsgren, Humble, Kim) ### DORA Metrics - **Deployment frequency**: how often code deploys to production - **Lead time for changes**: time from commit to production - **Change failure rate**: % of deployments causing failure - **Time to restore**: time to recover from production failure ### Performance Levels | Metric | Elite | High | |--------|-------|------| | Deployment frequency | Multiple times/day | Daily to weekly | | Lead time | < 1 hour | 1 day to 1 week | | Change failure rate | 0-15% | 16-30% | | Time to restore | < 1 hour | < 1 day | Use DORA metrics as baselines when assessing current state and ...