Terramate is a tool for managing multiple Terraform stacks.

The stack concept is not defined by Hashicorp's Terraform tooling but just a convention used by the Terraform community, so a stack can be loosely defined as:

A stack is a runnable Terraform Root Module that operates on a subset of the infrastructure's resources and has its own state.

Terramate provides ways to keep your Terraform code DRY and allows to define relationships between stacks and supports you to orchestrate Terraform commands in those stacks with minimal effort to get started in a non-intrusive way.

• Keep you code DRY: Avoid duplication by easily sharing data across your project.
• Code Generation: Generate valid Terraform Code to ensure that you can always enter a stack to run plain Terraform commands.
• Stack Change detection: Only execute commands in stacks that have been changed in the current branch or since the last merge.
• Module Change detection: Enhanced Change Detection allows to identifying stacks that have changes in local modules.
• Execute Any Command: Terramate is not a wrapper of Terraform but can execute any commands in (changed) stacks.
• Execution Order: Explicitly define an order of execution of stacks.
• Forced Stack Execution: Ensure specific stacks are run alongside other stacks.
• Pure HCL: All configuration of Terramate can be supplied in the well-known Hashicorp Configuraltion Language (HCL).

For more details on how this is achieved, please consider:

• Why Stacks ?
• Change Detection
• Config Overview
• Configuring A Project
• Sharing Data
• Code Generation
• Orchestrating Stacks Execution

If you're interested to know why we decided to build Terramate please consider our blog post: Introducing Terramate — An Orchestrator and Code Generator for Terraform.

Getting Started

Installing

Using Go

To install using Go just run:

go install github.com/mineiros-io/terramate/cmd/terramate@<version>

Where <version> is any terramate version tag, or you can just install the latest release:

go install github.com/mineiros-io/terramate/cmd/terramate@latest

Using a package manager

• macOS: You can install Terramate on macOS using Homebrew: brew install terramate

Using Release Binaries

To install Terramate using a release binary, find the appropriate package for your system and download it.

After downloading Terramate, unzip the package. Terramate runs as a single binary named terramate. Any other files in the package can be safely removed and Terramate will still function.

Finally, make sure that the terramate binary is available on your PATH. This process will differ depending on your operating system.

Using Docker

If you don't want to install Terramate on your host you can use Docker or Podman to run Terramate inside a container:

docker run ghcr.io/mineiros-io/terramate

Container images tagged with release versions are also provided. Click here for a list of the available container image tags.

Auto Completion

Terramate supports autocompletion of commands for bash, zsh and fish. To install the completion just run the command below and open a new shell session:

terramate install-completions

Project Setup

If you already have a project versioned on Git setting up Terramate is as easy as just installing Terramate. Terramate comes with sensible defaults so just using it inside a pre existent Git repository should not require any configurations.

The exception being repositories that have a default remote branch other than origin/main, in that case to make change detection work you will need to set a customized project configuration.

If you want to play around with Terramate from scratch locally you can also setup a local git repository:

playground=$(mktemp -d)
local_origin=$(mktemp -d)

git init -b main "${playground}"
git init -b main "${local_origin}"  --bare

cd "${playground}"
git remote add origin "${local_origin}"

echo "My Terramate Playground" > README.md

git add README.md
git commit -m "first commit"
git push --set-upstream origin main

# Start using terramate

Terramate can also work without any VCS setup, it will only require a Terramate configuration at the top level directory of the project

playground=$(mktemp -d)
cd "${playground}"

cat > terramate.tm.hcl <<- EOM
terramate {
  config {
  }
}
EOM

# Start using terramate

In a setup with no VCS change detection features will not be available.

You can also check our live example.