chainpad

Here's a sample document: https://extensions.standardnotes.org/collab/doc/741ec80a-366... Source is available here: https://github.com/standardnotes/collab-editor The editor relies on an impressive client-side library called ChainPad, which uses blockchains as inspiration for determining the authoritative document after conflicts or many simultaneous edits. Typically operational transformation algorithms and systems to manage conflicts are handled by the server, precluding the possibility for end-to-end encryption. However, ChainPad runs completely on the client-side, and is oblivious to the underlying text, thus allowing us to encrypt text client-side before broadcasting to other participants and the broadcast server. This is the first major effort I've seen for a real time client-side collaboration algorithm, and its use of a blockchain

Interesting idea. I think it's kind of odd to draw such a strong comparison to the Bitcoin blockchain. As the technical description [1] points out, the "chainpad" system discards most of the features and properties that make Bitcoin secure against malicious participants. That seems like a totally reasonable design decision for this application, but then describing it as a blockchain just adds confusion. In fact, the design seems to bear a much closer resemblance to the Bayou optimistic concurrency algorithm [2], with operational transformation as the underlying data model, and some extra crypto on top. [1]: https://github.com/xwiki-contrib/chainpad [2]: http://www.cs.utexas.edu/users/lorenzo/corsi/cs380d/papers/p...