atomic writes

[o0101]

 writes are already atomic because we use sync file operations and node is single-threaded.

lalaland1125 15 minutes ago 

File renames are atomic. This is a solved problem:

1. Write your updates to a copy of the file.

2. Do an atomic rename of that copy to the original.

but I like this because it's even safer say if something interrupts the write for whatever reason you already have a record without changing the original