vfs-sync

Three peers wired as a chain: A ↔ B ↔ C. A and C never talk directly — changes reach the far end because every edge runs its own sync.

Explorer Coverage GitHub npm

Try it: edit notes.md on A and on C without syncing in between, then hit Sync the whole chain — the newer edit wins and the other one is preserved as a (conflict …) copy.

For a chain that spans real backends — two OPFS folders, memory, and a folder from your disk — open the file explorer, an embeddable app built on the same library.