Opbox – CRDT based sync for text files on disk

In plain words

Opbox is an open-source daemon that enables real-time collaborative editing of text files and directories. It monitors local filesystem changes and syncs them across multiple users using CRDT technology, working with any text editor in an editor-agnostic way. Designed for developers and teams, it integrates alongside existing git repositories to share live changes between commits, turning directories of code and markdown files into shared workspaces.

written from the facts on this page · September 2026

From the sources

opbox is an experimental open-source daemon that syncs directories of plain text files between machines in real time — CRDT merges, any editor, end-to-end encrypted, offline-friendly.

opbox is an experimental daemon that syncs a directory of plain text files between machines in real time. It works at the filesystem level (meaning everyone can keep their own editor) and merges concurrent edits with CRDTs instead of conflict copies. Syncs end-to-end encrypted through a shared log on s2.dev , or self-host it with s2-lite . The opbox raison d'être basically. Our CRM is just folders of markdown docs, edited in some combination of Obsidian & various plain text editors, plus local agents. And git is too slow for this! You can keep using git at meaningful checkpoints, but use opbox to sync edits in between. opbox supports a .opboxignore file, and seeds it from .gitignore when…from opbox.dev

In the maker’s words, at launch

Hi! I’m one of the founders of s2.dev, and recently have been hacking on opbox, which is an open-source daemon that turns directories of text files (code, markdown, etc) into collaborative, multi-player workspaces. This started as a bit of an intellectual curiosity, to see if it was possible to do real-time sync at…

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