# Image Composer Tool (ICT)
[](./LICENSE)
[](https://github.com/open-edge-platform/image-composer-tool/actions/workflows/go-lint.yml) [](https://github.com/open-edge-platform/image-composer-tool/actions/workflows/unit-test-and-coverage-gate.yml) [](https://github.com/open-edge-platform/image-composer-tool/actions/workflows/zizmor.yml) [](https://github.com/open-edge-platform/image-composer-tool/actions/workflows/fuzz-test.yml) [](https://github.com/open-edge-platform/image-composer-tool/actions/workflows/trivy-scan.yml)
A command-line tool for building custom Linux images from pre-built packages. Define what you need in a YAML template, run one command, and get a bootable RAW or ISO image.
## How It Works
The diagram above illustrates the overall build flow and may show representative or planned provider/architecture
combinations. The table below lists the OS and architecture combinations that are currently supported.
## Supported Distributions
| OS | Distribution | Architecture |
|----|-------------|--------------|
| Azure Linux | azl3 | x86_64 |
| Edge Microvisor Toolkit | emt3 | x86_64 |
| Red Hat Compatible Distro | rcd10 | x86_64 |
| Wind River eLxr | elxr12 | x86_64 |
| Ubuntu | ubuntu24 | x86_64 |
| Ubuntu | ubuntu26 | x86_64 |
## Quick Start
### 1. Build the Tool
Requires Go 1.24+.
Recommended Ubuntu 24.04
```bash
git clone https://github.com/open-edge-platform/image-composer-tool.git
cd image-composer-tool
go build -buildmode=pie -ldflags "-s -w" ./cmd/image-composer-tool
```
This produces `./image-composer-tool` in the repo root.
Alternatively, use [Earthly](https://earthly.dev/) for reproducible production
builds (output: `./build/image-composer-tool`):
```bash
earthly +build
```
See the [Installation Guide](./docs/user-guide/get-started/installation.md) for Debian
package installation, prerequisite setup, and other options.
### 2. Install Prerequisites
```bash
# Required for image composition
sudo apt install systemd-ukify mmdebstrap
```
> Specific versions and alternative installation methods are documented in the
> [Installation Guide](./docs/user-guide/get-started/installation.md#image-composition-prerequisites).
### 3. Compose an Image
> **ISO images require the `live-installer` binary.** Build it before starting
> an ISO build:
>
> ```bash
> go build -buildmode=pie -o ./build/live-installer ./cmd/live-installer
> ```
>
> If you use `earthly +build`, both binaries are built automatically.
```bash
# If built with go build:
sudo -E ./image-composer-tool build image-templates/azl3/azl3-x86_64-edge-raw.yml
# If built with earthly:
sudo -E ./build/image-composer-tool build image-templates/azl3/azl3-x86_64-edge-raw.yml
```
That's it. The output image will be under
`./workspace/<os>-<dist>-<arch>/imagebuild/<config-name>/`
(or `/tmp/image-composer-tool/...` if installed via the Debian package).
### 4. Validate a Template (Optional)
Check a template for errors before starting a build:
```bash
./image-composer-tool validate image-templates/azl3/azl3-x86_64-edge-raw.yml
```
## Image Templates
Templates are YAML files that define what goes into your image — OS, packages,
kernel, partitioning, and more. Ready-to-use examples are in
[`image-templates/`](./image-templates/), grouped into one subdirectory per
distribution and catalogued in
[`image-templates/README.md`](./image-templates/README.md).
To build a variant of an image that already works, inherit it with `extends:`
rather than copying it — see
[`image-templates/COMPOSITION.md`](./image-templates/COMPOSITION.md).
A minimal template looks like this:
```yaml
image:
name: my-edge-device
version: "1.0.0"
target:
os: azure-linux
dist: azl3
arch: x86_64
imageType: raw
systemConfig:
name: edge
packages:
- openssh-server
- ca-certificates
kernel:
version: "6.12"
cmdline: "quiet"
```
To learn about template structure, variable substitution, and best practices,
see [Creating and Reusing Image Templates](./docs/user-guide/architecture/image-composer-tool-templates.md).
## Documentation
| Guide | Description |
|-------|-------------|
| [Installation Guide](./docs/user-guide/get-started/installation.md) | Build options, Debian packaging, prerequisites |
| [Usage Guide](./docs/user-guide/get-started/usage-guide.md) | CLI commands, configuration, shell completion |
| [CLI Reference](./docs/user-guide/architecture/image-composer-tool-cli-specification.md) | Complete command-line specification |
| [Image Templates](./docs/user-guide/architecture/image-composer-tool-templates.md) | Template system and customization |
| [Build Process](./docs/user-guide/architecture/image-composer-tool-build-process.md) | How image composition works, troubleshooting |
| [Secure Boot](./docs/user-guide/configuration/configure-secure-boot.md) | Configuring secure boot for images |
| [Multiple Repos](./docs/user-guide/architecture/image-composer-tool-multi-repo-support.md) | Using multiple package repositories |
## Get Help
- Run `./image-composer-tool --help`
- [Browse the documentation](https://docs.openedgeplatform.intel.com/2026.2/image-composer-tool/index.html)
- [Start a discussion](https://github.com/open-edge-platform/image-composer-tool/discussions)
- [Troubleshoot build issues](./docs/user-guide/architecture/image-composer-tool-build-process.md#troubleshooting-build-issues)
## Contribute
- [Open an issue](https://github.com/open-edge-platform/image-composer-tool/issues)
- [Report a security vulnerability](./SECURITY.md)
- [Submit a pull request](https://github.com/open-edge-platform/image-composer-tool/pulls)
## License
[MIT](./LICENSE)