1. Docker A containerization tool that packages your application with its dependencies. Why recommended: i. Consistency across environments (dev, test, prod) ii. Lightweight compared to virtual machines iii. Easily integrates with CI/CD pipelines iv. Portable across cloud/on-prem platforms Best Practices: i. Use a multi-stage Dockerfile to keep images small ii. Pin versions of base images to avoid unexpected changes iii. Regularly scan images for vulnerabilities (e.g., Trivy) iv. Avoid running as root inside containers 2. Kubernetes An orchestration platform for managing containerized applications. Why recommended: i. Automated scaling, healing, and deployment ii. Supports rolling updates and rollbacks iii. Strong ecosystem (Helm, Prometheus, Istio, etc.) iv. Cloud-agnostic: works on AWS, GCP, Azure, or on-prem Best Practices: i. Use Helm charts for templated deployments ii. Isolate workloads using namespaces iii. Set resource limits and liveness/readiness probes iv. Use RBAC and network policies for security Centralize logging and monitoring (e.g., EFK or Prometheus + Grafana) 3. Ansible An agentless configuration management tool. Why recommended: i. Simple YAML-based playbooks ii. Great for provisioning, configuring servers or apps iii. Works well in hybrid environments (VMs, containers, cloud) Best Practices: i. Use roles for reusable playbooks ii. Keep playbooks idempotent (running them twice doesn’t change outcome) iii. Use Ansible Vault to store secrets iv. Separate inventory files per environment (dev, prod) 4. Jenkins An extensible automation server for CI/CD. Why recommended: i. Huge plugin ecosystem ii. Supports pipelines-as-code with Jenkinsfile iii. Integrates with Git, Docker, Kubernetes, etc. Best Practices: i. Store Jenkinsfiles in source control ii. Use declarative pipelines for better readability and versioning iii. Use shared libraries for DRY pipelines