It might be interesting to persist snapshots to S3. It might be usable for small projects on Heroku/etc with ephemeral storage. It could be patched here (?) [1], but clearly there'd be a lot of issues with the long network call, how often to do it, how durable it really is, etc.

1: https://github.com/louischatriot/nedb/blob/b1abd34384cefea16...