Is Contact Book subject to the CLOUD Act?

No. The CLOUD Act compels US-based companies (or US subsidiaries) to hand over data they control, regardless of where it physically lives. Contact Book has no US entity, no US contracts, and no US-controlled infrastructure in the data plane. Stripe processes payment data and is US-headquartered, but that boundary is well-defined: payment metadata only, never your records.

Where exactly is my data stored?

On dedicated servers we operate ourselves, physically located in Germany. The audit log, attachments, embeddings - everything in the data plane - lives there. Backups stay within the same EU jurisdiction in different physical locations and roll off on a 30-day window. We deliberately do not name the exact data centre - knowing the rack does not buy the customer anything and would make operator changes a public event.

Do you log IPs or session metadata to a US service?

No third-party analytics, no Google Analytics, no Meta pixel, no third-country tag manager. The first-party device + session ledger lives in our own Postgres + Redis - same EU boundary as the rest of the data plane. Logs are operational only and rotate at 30 days.

What happens if I'm a customer outside the EU?

You can use Contact Book from anywhere. The data still lives in the EU; the request travels from your location to our servers and back. That's a posture choice on our side, not a geo-restriction on yours.

Contact Book

Compare

Contact Book: the EU alternative to Obsidian vault

Same job, hosted in the EU. Contact Book runs in Germany under German law - your data stays in EU jurisdiction end to end.

EU alternative

Personal CRM

Obsidian

Finn GlasCo-Founder + Engineering

·March 4, 2026·

1 min read

If your reason for moving off Obsidian vault is data sovereignty, the comparison gets simpler. Contact Book is hosted in Germany on infrastructure we operate ourselves - no US-headquartered company in the request path. The CLOUD Act does not reach what physically lives here.

At a glance

An Obsidian contacts vault is appealing for the same reason a paper notebook is: portable, private, never going away. The cost is everything that requires active prompting - cadence reminders don't fire, life events don't surface, the Sunday review doesn't have an overdue list. Contact Book is what you reach for when the vault stops doing the work.

EU jurisdiction

What 'EU-hosted' actually means here, end to end

Contact Book runs on dedicated machines we operate ourselves, physically located in Germany. There is no US-headquartered subprocessor in the request path - the data plane (your records, your files, your audit log) lives entirely in EU jurisdiction. Two third parties exist outside that boundary: Stripe (payment information only, under the EU-US Data Privacy Framework) and the mail relay for transactional email. Neither sees your records. Obsidian vault's setup is the variable - if their primary infra is US-based, the CLOUD Act applies regardless of what their privacy page claims.

Contact Book vs Obsidian vault: EU comparison

	Ours Contact Book	Theirs Obsidian vault
Hosted in Germany		Local
Local plain-text storage
Reminders that fire on time
Overdue dashboard
Mobile UX		Limited
Cross-device sync		DIY
Markdown export

When to pick which

Pick Contact Book when

You want a system that nudges you, not just stores what you wrote.

Pick Obsidian vault when

Plain-text local-first is non-negotiable.

You enjoy designing your own template + script suite.

EU-jurisdiction questions

Specific to where the data lives, who can subpoena it, and what crosses borders.

Start with Contact Book

Free plan, no credit card. We host in Germany. Export + delete are self-serve.

Written by

Finn Glas

Co-Founder + Engineering

Finn is one of the Co-Founders. He owns the engineering side, the infrastructure, and most of the late-night fixes that ship before anyone notices.

finn.glas at aicuflow dot comLinkedIn Website