We vibe-code apps that work.
every app was born from a need of my own. today I can finally build them — before, I only dreamed.
Smart home
I'm a practitioner. Here's what I actually use:
Energy arbitrage
The battery charges when the price is cheap and sells when it's expensive. Fully automatic — Home Assistant reads the spot price and decides on its own.
// cheap in, expensive outHA + spotPV-stop — a free project for PV park owners
When the spot price goes negative, the PV parks' output is cut. The park owner isn't paying to push power to the grid.
// Shelly smart relay cuts productionShellyPV + batteries vs NordPool, Tesla vs petrol
Real savings in euros per month. The sun charges the batteries and the Tesla — instead of an electricity and fuel bill I see a chart of money saved.
// charges from the sun or a cheap hour€/day/monthEMHASS forecast
I forecast tomorrow's energy balance — production, consumption, price — and the model works out the best plan for the whole day.
// tomorrow's best planEMHASSBalancing & capacity market
The home battery takes part in the balancing market (mFRR) and the capacity market (CAP) through Qilowatt (Kratt). Home Assistant offers the power to the market and pulls it back when the house needs it.
// the battery earns even while idlemFRR + CAP// Deye + Home Assistant + Tesla — they talk to each other.
Three things. All from my own needs.
Energy
Solar panels, batteries, electric car. Consumption optimised around the price of energy. A complete solution that makes money and gives peace of mind.
Smart home
Home Assistant, sensors, automations — they work even when the cloud is down. Your house, your rules.
Web
Websites and apps built around user intuition. No manual needed, the data is pre-filled.
Web apps
Heikki — entrepreneur, vibe-coder and AI enthusiast. I build apps that work, because I use them myself.
Book a call
Pick a slot from my calendar. Working hours are already set — just grab a time.
- 25 minutes, free
- Google Meet link included in the invite
- I reply myself, not an AI
Booking is handled by Google Calendar.