Syncthing is a continuous file synchronization program. It synchronizes files between two or more computers in real time, safely protected from prying eyes. Your data is your data alone and you deserve to choose where it is stored, whether it is shared with some third party, and how it’s transmitted over the internet.

Fluid Framework is a collection of client libraries for building distributed, real-time collaborative web applications. These libraries allow multiple clients to simultaneously create and operate on shared data structures using coding patterns similar to those used to work with local data.

Yjs is a CRDT implementation that exposes its internal data structure as shared types. Shared types are common data types like Map or Array with superpowers: changes are automatically distributed to other peers and merged without merge conflicts.

Yjs is network agnostic (p2p!), supports many existing rich text editors, offline editing, version snapshots, undo/redo and shared cursors. It scales well with an unlimited number of users and is well suited for even large documents.

A Scalable Server for Realtime Web Apps

• Stores and syncs data in realtime
• Built in node.js
• Works for browsers, backend & mobile
• Scales via clustering
• Exceptionally fast & easy to use
• Open Source and free (MIT License)

Kinto is a lightweight JSON storage service with synchronisation and sharing abilities.

Baïkal offers ubiquitous and synchronized access to your calendars and address books over CalDAV and CardDAV. Baïkal implements the current IETF recommendation drafts of these industry standards for centralized calendar and address book collections.