Cloud Parts

Infrastructure as code

Describe your infrastructure in files and let a tool build it.

6 technologies on this page ↓
Live model
What you’re watchingEach change to the code produces a plan, and the cloud API creates or updates exactly the resources that plan lists.

How it works

Instead of clicking through a console, you declare resources (networks, databases, queues, permissions) in files kept in git. The tool compares that desired state with what exists, shows a plan of what it will create, change or destroy, and then calls the cloud APIs to apply it. Environments become reproducible, changes get code review, and the history lives in version control.

Think of it as

An architect’s blueprint. Hand the same drawings to any builder and you get the same house, and every change starts as a revision on paper.

Reach for it when

  • Anything beyond a quick experiment
  • Keeping dev, staging and production identical
  • Reviewing infrastructure changes like code, with a plan preview

Think twice when

  • Editing tool-managed resources by hand in the console; that creates drift
  • Treating the state file casually; store it safely and lock it

A real example

A pull request adds a queue and lets a function read from it. CI runs terraform plan, the reviewer sees “2 to add, 1 to change”, and merging applies it to staging and then production.

Technologies

Specific products, and what each does differently.

AWS Cloud Development Kit (CDK)AWSDefine AWS infrastructure in TypeScript, Python, Java, C# or Go; the CDK turns it into CloudFormation templates and CloudFormation deploys them.HashiCorp PackerCommercialBuilds machine images (AMIs, Azure and Google images, VMware, Docker) from one HCL template, so every server starts already configured.HCP WaypointCommercialHashiCorp’s hosted internal developer platform: developers create apps and add databases from templates that run Terraform modules in HCP Terraform.OpenTofuOpen sourceThe open-source fork of Terraform, created after HashiCorp’s 2023 licence change: same HCL, same providers, `tofu` instead of `terraform`.SSTOpen sourceA TypeScript framework that defines a whole app, from Next.js front end to functions, containers and databases, in one config file and deploys it to your own AWS or Cloudflare account.TerraformCommercialThe most widely used infrastructure-as-code tool: declare resources in HCL, review a plan, and apply it through provider plugins.

What each provider calls it

AWS
CloudFormation, AWS CDK
Google Cloud
Infrastructure Manager
Azure
Bicep, ARM templates
Open source & others
Terraform, OpenTofu, Pulumi; SST for full-stack apps on AWS and Cloudflare; Packer for machine images; HCP Waypoint as a self-service portal on Terraform

In code · hcl

resource "aws_sqs_queue" "receipts" {
  name                       = "receipts"
  visibility_timeout_seconds = 60
}

resource "aws_s3_bucket" "media" {
  bucket = "example-media-prod"
}
# $ terraform plan  ->  Plan: 2 to add, 0 to change, 0 to destroy.

Worth exploring

Article· August 2022Deploying AWS Lambda functions using AWS Controllers for Kubernetes (ACK)Rajdeep Saha, AWS Compute BlogAWS’s step-by-step tutorial for managing Lambda functions as Kubernetes custom resources: install the ACK Lambda controller in EKS, give it IAM permissions through IRSA, then kubectl apply a Function manifest that points at code in S3. It explains why you might (one GitOps and RBAC model for pods and functions) but, being AWS’s own post, not the drawbacks.
WebsitePlatform tooling landscapePlatformEngineering.orgA filterable map of tools for building an internal developer platform. Each tool sits in one of five “planes” (developer control, integration and delivery, resource, observability, security) and a category such as IaC, CD pipeline, secrets or developer portal, with a one-line description. Vendors can submit their own tools, so treat it as a list of what exists rather than a ranking.
WebsitePlatformEngineering.orgThe Platform Engineering communityA community hub for teams that build internal developer platforms: a blog, a Slack workspace, the PlatformCon conference, courses, and a map of platform tooling.
ArticleUsing Lambda with KubernetesAWS Lambda Developer GuideAWS’s short docs page on managing Lambda functions through the Kubernetes API, with either AWS Controllers for Kubernetes (ACK) or Crossplane, and the use cases for each (reusing RBAC and IAM roles for service accounts, GitOps, tag policies). It covers provisioning only: the functions still run on Lambda, not in your cluster.
All resources →

Often confused with

CI/CD pipelinesVirtual private cloudsIdentity & access (IAM)Local cloud emulators
Where it came from1993–2023

In 1993 Mark Burgess, a theoretical physicist at the University of Oslo, wrote CFEngine to automate the upkeep of Unix machines. Fixes made by hand or with shell scripts grew cumbersome and haphazard, and every flavour of Unix needed its own. CFEngine took another approach: describe in one file how every host should be configured, and let the tool check and repair each machine as many times as needed, without human intervention.

That idea of declared, repeatable configuration spread with the growth of server fleets: Luke Kanies started Puppet in 2005 and Chef was released in 2009, both managing what was installed and configured on machines. Cloud computing then made the machines themselves, along with networks, load balancers and databases, something you could create with an API call. On February 25, 2011, AWS launched CloudFormation, which builds a whole stack of resources from one JSON template in the right order. Its launch post compared a template to a baking recipe, where precise ratios give “repeatable, high-quality results every time”.

CloudFormation only covered AWS. Terraform, released in 2014, used the same declarative approach across many clouds through provider plugins, with a plan step that shows exactly what will change before anything does. When HashiCorp moved Terraform to a source-available licence in 2023, its community fork OpenTofu was taken in by the Linux Foundation, and in 2025 it joined the CNCF.

Why it’s built this way

Declare the desired end state, not the steps
Step-by-step scripts break when a machine isn’t in the state the script expects. Describing the end result lets the tool work out what to change, and running it again changes nothing, which is what makes it safe to repeat.
Keep the definitions in version control
Infrastructure files can be reviewed, diffed and rolled back like application code, and the same template can create identical environments for development, testing and production.
Preview changes before applying them
With whole networks and databases at stake, Terraform shows a plan of every create, update and destroy and acts only on approval, so mistakes can be caught in review instead of in production.

Timeline

  1. 1993

    Mark Burgess creates CFEngine at the University of Oslo

  2. 2005

    Luke Kanies starts Puppet

  3. 2009

    Chef released

  4. 2011

    AWS CloudFormation launches in February with JSON templates

  5. 2014

    HashiCorp releases Terraform, cloud-agnostic, in July

  6. 2023

    Terraform relicensed; OpenTofu fork joins the Linux Foundation

Sources14

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