Comment by throwaway894345

For large, repetitive configurations (Kubernetes configs, CloudFormation templates, CI job configurations, etc) you often want ways to abstract and/or DRY your configurations. Kubernetes folks use mustache/jinja/Go templates via Helm, which is a real mess. CloudFormation builds its own (shitty) evaluation language on top of YAML. This presumably aims to improve on those sort of hacky solutions. I feel strongly that the "right" solution is either (1) generate a YAML config with Python/JS/etc or (2) use a terminating expression language (I think that may be what this is). Since (2) implies a much steeper learning curve for average developers, I opt for (1).