Fossil allows users to create private branches using the --private option to keep experimental or preliminary work local without sharing across clones. Private branches can later be merged into public branches to share changes, or synced between repositories using the --private flag on sync/push/pull commands with appropriate user permissions.
Livelymerge was an experimental self-sustaining object-oriented system that represented its entire state as an Automerge document to enable real-time multi-user collaboration. The researchers explored whether merging shared object memory across simultaneous users could work, discovering mixed but surprising results that suggested potential despite inherent challenges with object invariants.