Terraform is an open-source infrastructure as code tool by HashiCorp that lets you define and provision cloud infrastructure using a declarative configuration language called HCL.
Terraform uses a declarative approach to infrastructure management. You write configuration files in HashiCorp Configuration Language (HCL) that describe the desired end state of your infrastructure. Terraform then determines what actions need to be taken to reach that state.
The core workflow follows three steps: write your configuration, plan the changes to preview what will happen, and apply to execute those changes against your cloud provider.
Terraform enables teams to version control their infrastructure, review changes through pull requests, and apply consistent patterns across environments. Its provider ecosystem supports hundreds of services, making it a natural choice for multi-cloud strategies.
When combined with tools like Atmos, Terraform scales to manage complex multi-account AWS environments with dozens of components and environments.
Most teams start by defining their core networking and compute resources in Terraform, then gradually expand to cover DNS, monitoring, security, and other infrastructure layers. Cloud Posse maintains a library of production-ready Terraform modules that accelerate this process.
The companion to 'Terraform the Hard Way.' Same twenty-one crossroads, framed against what each one looks like under a framework that's already made the decisions. With concrete Atmos snippets at every step.
A guided checklist of every decision you'll make on the road from `terraform apply` to production. Not a recommendation — an education. Borrowed in spirit from Kelsey Hightower's 'Kubernetes the Hard Way.'
An internal developer platform is the icing on the cake — the reward for getting the foundation underneath into shape. Here's what I've learned about when the icing actually delivers, and why a framework matters more than the portal.
Teams keep telling themselves infrastructure is simple. 'It's just Terraform.' 'A contractor can clean it up.' Here's what those assumptions actually cost.
Open source Terraform module libraries are infrastructure's equivalent of npm and PyPI—battle-tested foundations that become even more critical when AI enters the picture.