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alright here it is, my hit-piece on CARs in atproto, with a big ecosystem survey

Trying to remember why I put the cids in there in the first place and feeling like I wouldn’t have done that…

wait wait, put the cids in there like... did you work on inventing CARs? (cool!!!!)

Yeah, wanting to have an index was a big part of it. But at that point in time I was very very sensitive to any extra unnecessary bytes in places they didn't need to be, having the entire cid in there when you could just rehash things is a waste.

I think the main reason is that you can't reconstruct the cid properly without knowing the cid header: what hash function to use and what codec the block is. I remember wanting to just include the prefix in there, but that got confusing