### Custom 'just' Recipe Example

Source: https://blue-build.org/learn/universal-blue

This demonstrates a basic 'just' recipe that prints a string to the console. 'just' is a command runner, and this example shows the fundamental syntax for defining a recipe named 'recipename'.

```just
recipename:
    echo "This is my recipe"
    echo "I can run commands here"

```

--------------------------------

### Rebase to Unsigned Universal Blue Image

Source: https://blue-build.org/learn/universal-blue

This command rebases an existing Fedora atomic installation to an unsigned Universal Blue image. It ensures proper signing keys and policies are installed before proceeding. The process requires a reboot to complete.

```bash
# example image details:
IMAGE_PATH=ghcr.io/octocat/weird-os
IMAGE_TAG=latest
# rebase command:
rpm-ostree rebase ostree-unverified-registry:$IMAGE_PATH:$IMAGE_TAG
# reboot to complete the rebase:
systemctl reboot

```

--------------------------------

### Rebase to Signed Universal Blue Image

Source: https://blue-build.org/learn/universal-blue

This command rebases an existing installation to a signed Universal Blue image, completing the installation process. It utilizes the `ostree-image-signed` specification for secure image deployment. A system reboot is necessary to finalize the rebase.

```bash
# example image details:
IMAGE_PATH=ghcr.io/octocat/weird-os
IMAGE_TAG=latest
# rebase command:
rpm-ostree rebase ostree-image-signed:docker://$IMAGE_PATH:$IMAGE_TAG
# reboot to complete the rebase:
systemctl reboot

```

--------------------------------

### Multi-line Bash Script 'just' Recipe

Source: https://blue-build.org/learn/universal-blue

This 'just' recipe executes a multi-line bash script. It includes a shebang to specify the interpreter and uses `set -euxo pipefail` for robust script execution. The recipe defines a variable and echoes its value.

```bash
scriptrecipe:
    #!/usr/bin/env bash
    set -euxo pipefail
    VAR="Hello, world!"
    echo $VAR # Hello, world!

```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.