[elamje]

I worked on this in 2018/19. It's a really hard problem, and the only people I've found doing it at scale is a small Norwegian company called https://piql.no. They encode large files into film and store it in the Arctic World Archive - and they did GitHub's Arctic Code Vault.

DNA storage is interesting, though can be damaged by radiation. Would love to see where you land with this project - it's one of the few cases where crypto may actually be the only real digital solution.

[Hasz]

I think boring, standard solutions are actually pretty effective. We use commercial cloud cold storage for primary backup, with a self-hosted cache layer in front to drive down cost. Commercial off-the-shelf storage is also the best characterized and has a proven track record.

NIST has some great reviews of the stability of optical media, and it’s quite good, done for the library of Congress.

DNA storage would enable some pretty crazy storage density, but ensuring there’s a compatible reader around in 30 years might be difficult