The Vapor Core Team would like to pitch MultipartKit to the SSWG. MultipartKit is a Swift library for encoding and decoding multipart form data based on SwiftNIO. It contains a C library used for the actual parsing of the request data and a Swift wrapper to integrate the C library with SwiftNIO.
Multipart is a popular mechanism for sending data to servers, especially when doing file uploads. It's supported by both browsers and HTTP libraries and we feel that having a Swift implementation in the SSWG is an important step for the ecosystem.
MultipartKit was originally built into Vapor for the release of Vapor 4 with the intention of splitting it out at a later date and pitching it to the SSWG so here we are! Since the implementation has been used in Vapor 4 it's fairly well battle tested and deployed.