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Lazyweb, is there a way, built into HTTP, to resume a partially completed upload?

What I'm finding searching the web seems to imply that there's not, and you would need to implement ad-hoc endpoints to query upload status, resume, and then combine the file chunks on the server. This seems surprising and frustrating to me; the feature is a must for reliable mobile uploads of media files, and this means it's impossible when I don't control the API... is it really so?