Playground

Hobby projects & experiments

Things I build on the side for the fun of it. Each one gets a short demo page — what it does, why I made it, and how it's put together.

Pocket Dossier

A single, reliable place for the personal information that matters — from product direction and UX to the core Swift architecture.

Live solar monitoring, day-ahead price planning, and surplus-driven home automation — connecting GoodWe SEMS, the OKTE market, and HomeKit.

A cited, bilingual guide to Japan's hot springs — spring sources, individual baths, the ten legal water types, and a relief map of where they are.