A high level diagram w/ links to files: https://eraser.io/git-diagrammer?diagramId=uttKbhgCgmbmLp8OF...
Specific flow of an OCR request: https://eraser.io/git-diagrammer?diagramId=CX46d1Jy5Gsg3QDzP...
(Disclaimer - uses a tool I've been working on)