Environment - Packages pre-installed in every
workload.
Required - Packages explicitly required in the
workloads.
Dependency - Runtime dependencies.
Base Buildroot
- Packages always present in the buildroot. Typically the 'build' group.
Buildroot level 1
- Packages needed to build all the above.
Buildroot level 2+
- Packages needed to build all the above. Basially just build dependencies of build
dependencies. There's multiple levels, each only present to build the previous level.