Getting started

In this tutorial you will create one standalone image definition and render the Image Customizer invocation without building an image.

1. Install tailor

Use a release binary or install from git:

cargo install --git https://github.com/frhuelsz/tailor tailor

Check it:

tailor --version

Expected shape:

tailor <version>+<commit>.<date>

2. Scaffold a standalone image

Create a new empty directory, then run:

mkdir solo-demo
cd solo-demo
tailor init solo simple

Expected output includes:

created .../solo-demo/image.yaml
Scaffolded standalone image `solo`. Try: tailor validate

The simple template creates only ./image.yaml; there is no tailor.yaml. In standalone mode tailor uses its built-in default Image Customizer toolchain: mcr.microsoft.com/azurelinux/imagecustomizer:latest.

3. Read the image definition

Open image.yaml:

name: solo
outputs:
  - format: cosi
base:
  azureLinux:
    version: "3.0"
    variant: minimal-os
config:
  os:
    hostname: solo
    packages:
      install:
        - openssh-server
    services:
      enable:
        - sshd

Top-level keys are tailor's. Everything under config: is Image Customizer configuration and is passed through opaquely.

4. Validate

tailor validate

Expected shape:

✓ solo                         1 cell(s) valid

5. Dry-run the build

tailor build --dry-run

Expected shape:

1 cell(s) (dry-run)
...
imagecustomizer ... --config-file ... --output-image-format cosi ...

--dry-run renders the build plan — the container/Image Customizer invocation — and prints it without starting a container. It contacts no container engine, so it works with no Docker daemon. Remove --dry-run when you have Docker daemon access and want to build the artifact.

Next step

Learn matrix builds in Your first matrix.