I started this project painfully aware that there are probably a handful bash wrappers around curl doing the same stuff, so this is NIH syndrome incarnate.
Still, I was interested in how much effort it would take to write a one-shot http client plus custom multipart/form-data encoding logic. Turns out, it’s not too bad, but reading through the IETF specifications and ironing out quirks can be tedious, and makes me wish we had a more straightforward and modern way to upload files.