EC2 Image Builder

Teams that need a standardized, patched, hardened base image usually build it by hand: launch an instance, run a script, install an agent, snapshot an AMI, repeat every month. It’s slow, error-prone, and undocumented. EC2 Image Builder turns that into a declarative pipeline: define a source image plus a list of components (install steps, CIS hardening, tests), and it builds the image in a throwaway environment, runs your validation tests, and distributes the finished AMI (and optionally a container image) to the Regions and accounts you specify — on a schedule or on a trigger.

• Pipelines, recipes, and components are Regional resources; the build runs in a single AZ in that Region on a temporary EC2 instance.
• Distribution settings are how one build fans out cross-Region and cross-account — the output AMI is copied to each target Region, and launch permissions can be shared with other accounts (or an AWS Organization).
• Output can be an AMI, a container image pushed to ECR, or both from the same recipe.

graph LR
BASE["Source image (Amazon Linux 2023)"] --> RECIPE["Image Recipe (base + components)"]
RECIPE --> BUILD["Build stage (temp EC2, run components)"]
BUILD --> TEST["Test stage (validation components)"]
TEST --> DIST["Distribution settings"]
DIST -->|"AMI"| R1["Region us-east-1"]
DIST -->|"AMI copy"| R2["Region eu-west-1"]
DIST -.->|"launch permission"| ACC["Other AWS accounts / Org"]
classDef stage fill:#e8f0fe,stroke:#3b82f6,stroke-width:2px,color:#173a70
classDef out fill:#eaf7ec,stroke:#2e8b3d,stroke-width:2px,color:#1a3d20
class BUILD,TEST stage
class R1,R2 out

Image Builder itself is free. You pay only for the resources a pipeline run consumes: the temporary EC2 instance during build and test, the EBS snapshots backing the resulting AMI, S3 for logs, ECR if you output container images, and cross-Region data transfer when copying AMIs. Runs are short, so the cost is small and predictable relative to the compliance value.

• Trigger phrases: “automate golden AMI creation,” “keep base images patched and hardened,” “consistent images across Regions and accounts,” “test images before release” → EC2 Image Builder.
• It integrates with AWS Organizations, License Manager, and Systems Manager (SSM Agent runs the components), and can enforce that only approved, tested images are distributed.
• Use it with Auto Scaling launch templates — point the template at the latest Image Builder AMI (via SSM Parameter Store) so new instances always boot the current golden image.
• Image Builder vs a Packer script: same outcome, but Image Builder is managed, has a test stage, native multi-Region/account distribution, and scheduled rebuilds without you running a CI job.
• CIS hardening and STIG components are AWS-managed and can be dropped straight into a recipe.