Essential Infrastructure as Code teaches patterns for scaling systems and supporting infrastructure for mission-critical applications. The book is fullof flexible automation techniques and universal principles that are easy toapply to almost any use case, from data centers, to public cloud, to software-as-a-Service.  The book is full of techniques that work whether you''re managing your personal projects or making live network changes across a large enterprise. Infrastructure as Code (IaC) replaces time-consuming manual provisioning and configuration with automation via configuration managers or provisioning tools like Hashicorp Terraform. Managing your infrastructure as code makes it easy to test changes and implement new features, scale systems without downtime or operational toil, and rapidly roll back mistakes.