Who is behind this?

I am Julian Haag from Ilsfeld in southern Germany. In my day job at Haag Automation I work on energy management and home automation. xmoo.app is where the side products end up: small tools that save me work and might save you some too.

Until October 2026 the site was called xmoo.de. Old addresses redirect to the same page on xmoo.app.

How the tools are made

Every tool starts with a question I had myself. They are built with the help of artificial intelligence (Claude Code by Anthropic); I review and release them. Each tool explains what it is good for, how it calculates and where its limits are. Figures and rules a tool relies on come with a source.

Wherever possible the tools run in your browser and what you enter stays with you. If a tool needs the server, it says so on the tool page and in the privacy policy.

How xmoo.app is funded

The site is free and shows ads from Google AdSense in return. There are also affiliate links to Amazon – only to things mentioned in a tool’s text, and always marked with an asterisk. If you buy something through one, I get a small commission; the price stays the same for you (privacy policy, section 6).

Other projects of mine

• Haag Automation – articles on electricity, heating and Home Assistant, with primary sources (in German).
• Sektor112 – a fire-brigade dispatch game for the browser: run incidents from the control room and build up your own station. Still in development (in German).

Contact

Found a mistake or want a tool? Write to me at julian@haag-automation.com – in English or German.