This is obviously not a spec, but it's as close as it gets to the API that I would like. And it's got Daniel Bleichenbacher listed as author so it's got my vote

This is obviously not a spec, but it's as close as it gets to the API that I would like. And it's got Daniel Bleichenbacher listed as author so it's got my vote. I couldn't find any on disk spec though at all though which is a little odd: https://github.com/google/tink https://github.com/google/tink Very cool project.