HashiCorp Packer: Automating Machine Images for DevOps and DevSecOps

Source: Dev.to

Overview of the Tool

HashiCorp Packer is a tool for automating the creation of machine images for various platforms (cloud, virtual machines, containers) using a single source configuration. It lets you define how to build images once and produce identical artifacts for AWS, Azure, GCP, Docker, VMware, and other environments. Packer focuses on immutable infrastructure by generating pre‑configured, deployable images (e.g., AMIs, container images) that can be reused across environments.

Key Features

1. Multi‑Platform Image Builds – Consistent images for multiple platforms (cloud providers and virtualization systems) from a single template.
2. Templates Using HCL/JSON – HashiCorp Configuration Language (HCL) or JSON to define builders, provisioners, and post‑processors.
3. Parallel Build Support – Build multiple images concurrently.
4. Provisioners and Plugins – Extensible via plugins and provisioners.
5. Integration With CI/CD – Works seamlessly in automated pipelines (GitHub Actions, Azure DevOps, Jenkins, etc.).
6. Golden Image Management – Enables creation and management of trusted “golden” images.

How It Fits into DevOps / DevSecOps

DevOps Alignment

• Infrastructure as Code (IaC) – Packer codifies image builds in configuration files, aligning with IaC principles.
• CI/CD Integration – Produces images as pipeline artifacts, fitting into automated build pipelines.
• Immutable Artifacts – Bakes software and dependencies into images, reducing configuration drift during deployments.

DevSecOps Alignment

• Security Standards Built In – Automates image builds with security configurations and compliance checks, enforcing secure baselines early in the lifecycle.
• Repeatable Secure Builds – Guarantees the same hardened image is used across environments, eliminating manual image setup.

Programming Language

• Written in: Go (Golang) – a performant language that produces standalone binaries across platforms.
• Configuration: Packer templates use HCL (preferred) or JSON.
• Ecosystem: Plugin integrations and extensions are also designed around Go.

Parent Company

• Developer: HashiCorp, Inc. – a company specializing in infrastructure automation tools.
• Related Tools: Terraform, Vault, Consul, Nomad, and others.
• Acquisition: HashiCorp was acquired by IBM in 2025 (closing February 2025) and now operates as part of IBM.

Open Source or Paid?

The core Packer tool is free and open source, while enterprise or cloud‑hosted capabilities may involve cost.