About OzyCore GmbH

We build focused compliance tools for the German Mittelstand.

e-Rechnung Inbox is our first product. It exists because the German e-invoicing mandate that took effect on 1 January 2025 left millions of small businesses with a problem no one wanted to solve cleanly: how to receive, validate and archive structured invoices without buying an ERP, hiring a consultant or changing accounting software.

We chose this problem because it's narrow, technical, and underserved. We are not building another all-in-one accounting platform. We are not building AI magic. We are building the missing piece that every business in Germany suddenly needs — and we are building it the way German infrastructure has always been built: deeply, correctly, and for the long term.

What we believe

• — A single-purpose tool executed with depth beats a ten-feature platform executed with breadth.
• — Compliance is not a burden to abstract away. It is the product. We treat GoBD, EN 16931 and XRechnung conformance as the core, not as a footnote.
• — Our hosting posture is Germany/EU regions. Primary systems run in Frankfurt; sub-processor and support flows are documented transparently.
• — Tax advisors are not a channel. They are a partner class. We build for them and with them from day one.

The company

Ramazan Özdemir

Co-founder · Finance & Administration

Ramazan Özdemir runs his own accounting practice. e-Rechnung Inbox was co-developed out of that practice: the workflows the product maps are the workflows of his daily work.

Consulting in German and Turkish

Dr. Yusuf Yılmaz

Co-founder · Product & Engineering

Dr. Yusuf Yılmaz is responsible for product and engineering — from EN 16931 validation and archiving to the DATEV handoff.

Consulting in Turkish and English