in my opinion, it will take three years of slow steady progress, divide it into four stages, this year end, next year end, and you will be good by next to next year end.
reduce reliance on third party, this will support you when the third party producers change their API and you will save time in not making changes adapting to theirs.
theory- light leaks through retinal neron in eyes. using retinal scan that is used to neasure neoropathy for diabetics patience or glucoma testing machine concept.