If the input configuration of a Customize-engine is a Promise, it is resolved before passing it to the engine's preprocessor. Inner Promises are not resolved.
If the input configuration of a Customize-engine is a Promise, it is resolved before passing it to the engine's preprocessor. Inner Promises are not resolved.

nknapp/customize-engine-handlebars,nknapp/customize-engine-handlebars,bootprint/customize-engine-handlebars,bootprint/customize-engine-handlebars