In case you haven't seen the UF2 file format, it's specifically designed to be robust w.r.t ensuring that the content makes it to the target intact despite common OS quirks.

https://github.com/microsoft/uf2

  - Data is divided into 512 byte blocks, which lines up with the mass storage transfer size.
  - Each block has an identifying magic sequence, a payload address, and size, which can be used to identify the destination.
    - This allows the emulated storage to ignore metadata blocks and to handle out-of-order and repeated blocks.