I think NilFS [0] fits your description, though it is somewhat obscure. It creates a checkpoint with every write, which can mounted after being turned into a sn

I think NilFS [0] fits your description, though it is somewhat obscure. It creates a checkpoint with every write, which can mounted after being turned into a snapshot. Although the website seems to have not been updated in a while, it's mailing lists appear to be active. [1] https://nilfs.sourceforge.io/en/ https://nilfs.sourceforge.io/en/ [0] https://marc.info/?l=linux-nilfs https://marc.info/?l=linux-nilfs [1]