Only the low level binary mangling parts. Does not come with the parser or codegen segments.
https://github.com/IcedQuinn/protobufcore (gitea link somewhen)
Thanks for your work, although I'm curious - are there any reasons you weren't satisfied with already existing https://github.com/PMunch/protobuf-nim or https://github.com/oskaritimperi/nimpb ?
P.S.: Please add a LICENSE file to your repository, otherwise your code can't be used by other projects.