A practical guide to containerizing Rails 8.1 applications using Docker and Kamal 2. Covers multistage builds to reduce image size by 50-70%, running containers as nonroot users, scanning for CVEs with Docker Scout in CI, configuring Puma for containerized environments, zero-downtime deployments with health checks, database migration hooks, horizontal/vertical scaling strategies, and a pre-merge checklist to enforce security and correctness standards.
Table of contents
IntroductionUnderstanding Rails Docker SetupThe Rails Dockerfile ExplainedDeployment Best PracticesSecurity Best PracticesDatabase ManagementHealth ChecksProduction OptimizationScaling StrategiesMonitoring and DebuggingCI/CD IntegrationCommon PitfallsPre-merge ChecklistConclusion384 Impressions