Update nexus: fix conflicts and sync local changes

wiki/concepts/Rollback-Rate.md

@@ -1,74 +1,74 @@
-# Rollback Rate
-
-## Definition
-Rollback Rate is the proportion of deployments that are reverted (rolled back) to a previous stable version after being deployed to production. It measures how often deployments fail to the point where reverting becomes necessary.
-
-The DevOps Maturity Model explicitly lists Rollback Rate as one of the metrics for measuring DevOps maturity.
-
-## Why Rollback Rate Matters
-
-A high rollback rate indicates:
-- Deployment quality issues
-- Insufficient testing before deployment
-- Gap between staging and production environments
-- Unstable or risky deployment processes
-
-A low rollback rate indicates:
-- High confidence in the deployment pipeline
-- Comprehensive pre-production testing
-- Stable deployment processes
-
-## Across DevOps Maturity Levels
-
-| Maturity | Rollback Rate Characteristic |
-|----------|------------------------------|
-| Phase 1 | High rollback rate — manual deployments, no automated testing, siloed teams, manual infrastructure |
-| Phase 2 | Improving — automation reduces some risks, but manual interventions still cause rollbacks |
-| Phase 3 | Lower — automated infrastructure and security scans reduce failures before deployment |
-| Phase 4 | Reduced — performance testing, immutable infrastructure, dependency vulnerability management |
-| Phase 5 | Minimal — zero human intervention, real-time decisions, rollback automation for fast recovery |
-
-## Relationship with Other Metrics
-
-### Rollback Rate and Change Failure Rate
-- **Change Failure Rate**: All deployments that cause failures (regardless of rollback)
-- **Rollback Rate**: Only deployments where the team explicitly chose to roll back
-
-A high CFR but low Rollback Rate could mean failures were fixed without rollback. A low CFR but high Rollback Rate suggests teams are overly cautious.
-
-### Rollback Rate and MTTR
-- Rollback is often a strategy for reducing MTTR
-- Fast rollback mechanisms enable quick recovery
-- Organizations with mature CI/CD pipelines have both low rollback rates AND fast rollback capabilities
-
-## How to Reduce Rollback Rate
-
-### Technical Strategies
-- Comprehensive pre-production testing
-- Feature flags for gradual rollouts
-- Canary deployments (route small % of traffic to new version)
-- Blue-green deployments
-- Comprehensive observability to detect issues before users notice
-- A/B testing in production
-
-### Process Improvements
-- Small batch deployments to limit blast radius
-- Strict deployment criteria (all tests green, no open severity-1 bugs)
-- Deployment freeze periods for critical systems
-- Change advisory board for high-risk changes
-
-### Cultural Factors
-- Psychological safety to admit when a deployment is failing
-- Clear criteria for when to rollback vs fix-forward
-- Blameless post-mortems to learn from rollbacks
-- On-call engineers empowered to make rollback decisions
-
-## Sources
-- [[sources/devops-maturity-model-from-traditional-it-to-advanced-devops.md]]
-
-## Related Concepts
-- [[concepts/Change-Failure-Rate]]
-- [[concepts/MTTR]]
-- [[concepts/DORA-Metrics]]
-- [[concepts/Continuous-Deployment]]
-- [[concepts/DevOps-Maturity]]
+# Rollback Rate
+
+## Definition
+Rollback Rate is the proportion of deployments that are reverted (rolled back) to a previous stable version after being deployed to production. It measures how often deployments fail to the point where reverting becomes necessary.
+
+The DevOps Maturity Model explicitly lists Rollback Rate as one of the metrics for measuring DevOps maturity.
+
+## Why Rollback Rate Matters
+
+A high rollback rate indicates:
+- Deployment quality issues
+- Insufficient testing before deployment
+- Gap between staging and production environments
+- Unstable or risky deployment processes
+
+A low rollback rate indicates:
+- High confidence in the deployment pipeline
+- Comprehensive pre-production testing
+- Stable deployment processes
+
+## Across DevOps Maturity Levels
+
+| Maturity | Rollback Rate Characteristic |
+|----------|------------------------------|
+| Phase 1 | High rollback rate — manual deployments, no automated testing, siloed teams, manual infrastructure |
+| Phase 2 | Improving — automation reduces some risks, but manual interventions still cause rollbacks |
+| Phase 3 | Lower — automated infrastructure and security scans reduce failures before deployment |
+| Phase 4 | Reduced — performance testing, immutable infrastructure, dependency vulnerability management |
+| Phase 5 | Minimal — zero human intervention, real-time decisions, rollback automation for fast recovery |
+
+## Relationship with Other Metrics
+
+### Rollback Rate and Change Failure Rate
+- **Change Failure Rate**: All deployments that cause failures (regardless of rollback)
+- **Rollback Rate**: Only deployments where the team explicitly chose to roll back
+
+A high CFR but low Rollback Rate could mean failures were fixed without rollback. A low CFR but high Rollback Rate suggests teams are overly cautious.
+
+### Rollback Rate and MTTR
+- Rollback is often a strategy for reducing MTTR
+- Fast rollback mechanisms enable quick recovery
+- Organizations with mature CI/CD pipelines have both low rollback rates AND fast rollback capabilities
+
+## How to Reduce Rollback Rate
+
+### Technical Strategies
+- Comprehensive pre-production testing
+- Feature flags for gradual rollouts
+- Canary deployments (route small % of traffic to new version)
+- Blue-green deployments
+- Comprehensive observability to detect issues before users notice
+- A/B testing in production
+
+### Process Improvements
+- Small batch deployments to limit blast radius
+- Strict deployment criteria (all tests green, no open severity-1 bugs)
+- Deployment freeze periods for critical systems
+- Change advisory board for high-risk changes
+
+### Cultural Factors
+- Psychological safety to admit when a deployment is failing
+- Clear criteria for when to rollback vs fix-forward
+- Blameless post-mortems to learn from rollbacks
+- On-call engineers empowered to make rollback decisions
+
+## Sources
+- [[sources/devops-maturity-model-from-traditional-it-to-advanced-devops.md]]
+
+## Related Concepts
+- [[concepts/Change-Failure-Rate]]
+- [[concepts/MTTR]]
+- [[concepts/DORA-Metrics]]
+- [[concepts/Continuous-Deployment]]
+- [[concepts/DevOps-Maturity]]