About Sync-in
Sync-in is a French 🇫🇷, sovereign, open-source collaborative platform for file storage, sharing, synchronization, and collaboration. It is intended for individuals, businesses, public-sector entities, and institutions seeking a controlled, scalable platform aligned with their operational requirements.
Our ambition is to contribute to the self-hosting ecosystem with a collaborative platform built on a different architecture, designed to prioritize performance, simple deployment and administration, while giving users lasting control over their data.
In Sync-in, sovereignty means users and organizations retain control over their data. Sharing a document does not mean giving up control over it: files remain attached to their owner, with controllable and revocable access, even when they are integrated into a collaborative space.
Project origins
Sync-in has been developed for more than ten years by its founder and engineer Johan Legrand (LinkedIn).
Over time, the solution has evolved with the support and feedback of several companies, shaped by concrete needs around storage, sharing, synchronization, and administration. Its development is also supported by a team including Thibault Signor and Alex Zalo.
Sync-in has been published as open source on GitHub since 2025 and is now used by individuals, companies, and public-sector organizations. The solution continues to evolve with a focus on being useful, responsible, and community-driven.
Why Sync-in
Rather than building Sync-in on an existing architecture, we chose to start from a blank slate. This approach allowed us to design a platform where storage remains under the user's control, files remain directly readable and usable on the file system, and access rules are applied consistently regardless of the access method: web interface, WebDAV, synchronization, collaborative editing, or API.
This architecture prioritizes performance for file operations, limits unnecessary data duplication, simplifies deployments, and provides stronger data reversibility.
These principles are detailed in our architecture documentation:
Our values
The development of Sync-in is guided by several key principles:
- Open-source: the code is public and can be audited, adapted, and improved.
- Digital sovereignty: you retain control over your documents, their access rules, your data, and your infrastructure.
- Transparency: the project's workings and evolution are documented and accessible.
- Responsibility and accessibility: the solution is designed to be useful, sustainable, and suitable for organizations of all sizes and contexts.
Professional Services
Alongside the open-source project, Sync-in is also a French company that provides a professional framework to support organizations in its adoption, integration, and operation.
For organizations adopting it in a professional context, we offer:
- partnerships for integrators, hosting providers, and organizations building an offer around Sync-in;
- sponsorship opportunities to support the project's visibility and development;
- dedicated support and professional services to facilitate platform deployment, operation, and integration.
These offers are intended for organizations that need a professional framework around Sync-in and can be discussed in a dedicated conversation.
Clear Framework
Sync-in is released under the AGPLv3 license, ensuring access to the source code and the ability to use or adapt the solution — including in
hosted-service scenarios — in compliance with the license.
The Sync-in® name, logo, and visual identity are protected. Their use in a commercial context is governed by our Trademark Policy and
our Partner Program.