We have discussed how to customize images using the append file on images, or using configuration files. These techniques are useful in some use cases, yet they could become a hassle in cases where we are dealing with logs of packages and we want to use these packages with more than one image type. In such cases, we will be performing duplications, which are certainly not clean. To avoid such cases, packagegroups comes into play. The idea is to keep these lists of packages separate from image append files so that they can be used across multiple images.

This is a specialized recipe .bb file with the following features. Again, it will reside in the top-level directory of our layer/recipes-*/packagegroups/<packagegroup>.bb file: