100% Open Source

Build your OUIS

System Information Open Source Urbanized.

Bunker assembles your 100% open source OUIS, a sovereign collaborative and office suite, an alternative to Microsoft 365 and Google Workspace, hosted in Europe. Mail, drive, video, ERP, CRM. Each building block is pre-configured, hosted on your own servers and yours to bring back in-house whenever you decide.

Microsoft 365 and Copilot stay under the US CLOUD Act

An office suite published in the US stays under US law, even hosted in Europe. The CLOUD Act lets US authorities order Microsoft to produce your data, wherever the servers sit, and Copilot adds exposure because it processes your content in clear text to generate its answers.

In March 2024, the European Data Protection Supervisor ruled the European Commission's use of Microsoft 365 non-compliant with data-protection rules. A sovereign collaborative suite, hosted in Europe and reversible, removes the problem at the root.

« No, I cannot guarantee it. »

Anton Carniaux, Director of Public and Legal Affairs, Microsoft France

Under oath before the French Senate inquiry committee, 10 June 2025.

Understand the CLOUD Act and the sovereign alternative →
Our philosophy

"Open source always wins in the end."

For each open source solution deployed, Bunker contributes 5% of its revenue to the projects involved.

Commitment
5%

Contributed to open source

Revenue redistributed to open source projects your IS depends on. We guarantee the sustainability of your software components.

Supported projects:
+21
0

Vendor lock-in

Complete freedom to migrate or change providers at any time.

Digital commons

Contribution to the ecosystem and European digital commons.

Our tools catalog

A selection of open source tools, ready to be deployed on your infrastructure

Ready to build your OUIS?

Let's discuss your needs and design together an 100% open source information system, sovereign and adapted to your organization.