Most programmers, and especially the hipsterish HN crowd, simply cannot be trusted to write correct file manipulation code. In general, anything they produce will be riddled with race conditions and erroneous assumptions (e.g., that rename works cross-device, that close cannot fail) and that breaks in rare but possibly catastrophic circumstances.

The solution is copy-on-write file systems such as ZFS and Btrfs that ensure neither data nor meta-data are ever altered in-place and the reuse of correct file manipulation code (written by adults) rather than rolling your own, either from a library or something higher-level like SQLite.