Phase 5 — DevOps, Containers, IaC, Observability & System Design

Code is not done when tests pass on your laptop; it is done when it runs reliably in production, deploys without downtime, and wakes the right person up when latency spikes. Phase 5 covers Docker, CI/CD, Kubernetes, Ansible, Prometheus, Grafana, Sentry APM, and System Design interviews.

Modules & Lessons

01 — Containers, CI/CD & Orchestration (Docker & Kubernetes)

01-docker-and-compose-in-production — Linux namespaces/cgroups, multi-stage Dockerfiles, non-root security, layer caching, and Compose healthchecks
02-ci-cd-pipelines — GitHub Actions: automated linting, matrix test suites with service containers, image builds, and zero-downtime migration rollouts
03-kubernetes-fundamentals — Pods, Deployments, Services, Ingress, ConfigMaps/Secrets, liveness/readiness probes, and HPA scaling

02 — Infrastructure as Code (Ansible)

01-ansible-playbooks-and-roles — Inventories, idempotent modules, roles, Ansible Vault, and automated Linux server hardening & deployment

03 — Observability, Monitoring & APM (Prometheus, Grafana, Sentry)

01-structured-logging-and-sentry — JSON structured logging, context vars, Sentry SDK integration, breadcrumbs, and issue triage
02-prometheus-and-grafana — Counter/Gauge/Histogram metrics, RED & USE methods, PromQL queries, and building actionable Grafana dashboards
03-distributed-tracing-and-apm — OpenTelemetry spans, context propagation across FastAPI/Celery/Postgres/gRPC, and flamegraph profiling

04 — System Design Mastery

01-capacity-estimation-and-scaling — Latency numbers every engineer must know, back-of-the-envelope math, read replicas, sharding, and consistent hashing
02-system-design-case-studies — End-to-end architecture blueprints: Distributed Rate Limiter, Webhook Delivery Engine, Real-time Notification System, and High-Volume Log Pipeline

Capstone Milestone: `pulseforge/` v1.0 (Production Release)

Package PulseForge for production with multi-stage Dockerfiles, GitHub Actions CI/CD, Kubernetes manifests, an Ansible deployment playbook, Prometheus/Grafana dashboards, Sentry error/APM instrumentation, and a locust/k6 load-testing benchmark report.