JCasC requires that top level configuration sources are all defined in a single block. Anything defined outside of that gets removed from the configuration. What this means in practice is that we need to have some way for our customers to easily add new configurations without having to pick through giant config files (all managed files are going to end up in a single yaml hash same as all clouds!).

We need an lftools tooling that can take directory structures of files and merge them into single yaml outputs which are put in the correct place on disk. This utility will be used by a cron job (RELENG-????) that will be run on the production and sandbox Jenkins nodes to regularly pull the ci-managment repository. If there are changes to the configuration system files it would then need to have this utility run over the customer supplied configuration and generate the actual files that need to be layed down on disk.