WIP diagram - needs more work to put it into context of buildstream
graph LR;
bst_file --> |sources| sources
bst_file --> |depends| cache(cached artifacts)
cache(cached artifacts) --> |already built| artifact
sources --> | build| artifactgraph LR;
bst_file --> |sources| sources
bst_file --> |depends| cache(cached artifacts)
cache(cached artifacts) --> |already built| artifact
sources --> | build| artifact