What it does
Packer is a command-line image builder that uses configuration templates to create machine images and other build artifacts. A template selects a builder and its inputs, then can apply provisioning steps before producing an artifact. Teams use it to standardize images for more than one target environment; infrastructure provisioning and application deployment remain separate workflow stages.
Define the image, then build an artifact
HashiCorp's Docker tutorial begins with a Packer template written in HCL. The template describes an image source and the Docker builder; the user then runs the documented build command to generate an artifact. For a larger environment, use the builder and plugins for each target platform and keep secrets such as cloud credentials outside the template. The command reference explains that packer build executes the builds in a template and outputs the resulting artifacts. Packer is the image-creation step, not the deployment controller: a pipeline can build a machine image with Packer and then hand that artifact to a separate provisioning or release tool. This distinction is useful when a team wants repeatable base images but already has its own infrastructure-as-code and deployment workflow. The repository's license file identifies Packer 1.10.0 and later under Business Source License 1.1, with a production-use grant and restrictions on offering the software to third parties as a competing hosted or embedded product. Review that version-specific license before distributing or embedding Packer. The official Packer pricing page returned HTTP 429 during research, so no price or billing classification is asserted.
Strengths
- A template can describe repeatable image builds and separate build logic from deployment configuration.
- The build command reference documents parallel builds and output artifacts from the configured template.
- The official tutorial demonstrates the image-building workflow with a Docker target.
Watch out for
- Each target platform needs a suitable builder and configuration; Packer does not replace infrastructure provisioning or release deployment.
- The current repository license is BSL 1.1 with specific additional-use terms, so redistribution and competing hosted or embedded use need review.
Best for
- Platform teams building standardized machine images for multiple deployment targets
- CI workflows that produce versioned image artifacts before a separate deployment stage
Sources
- Packer | HashiCorp Developer (Oct 25, 2026)
- Build an image | Packer | HashiCorp Developer (Oct 25, 2026)
- packer build command reference | Packer | HashiCorp Developer (Oct 25, 2026)
- hashicorp/packer (Oct 25, 2026)
- Packer BSL 1.1 License | hashicorp/packer (Oct 25, 2026)