A chunk of me online
Notes on WordPress, Symfony, Linux, home automation and free software. Written from the trenches.
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Connecting your app to banks costs €7,200 a year before you have a single customer
I asked for prices so Cuéntamo could read my bank: €600 a month, €7,200 a year in fixed cost before the first customer. Why bank aggregation has no ramp —and the open-source alternative I built for any finance app.
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Your data, in your hands: why I built Habeas
Although the GDPR recognizes the right to data portability, most companies still do not provide practical ways to export personal data. Habeas solves this with a browser extension that extracts data directly from the user’s authenticated session, without intermediary servers or shared credentials, using auditable YAML adapters for each service.
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Why I Built My Own Personal Finance App
Managing finances as a self-employed professional in Spain often means juggling spreadsheets, multiple apps, and constant uncertainty. After years of searching for a tool that combined cash flow forecasting, tax management, and personal finances, I ended up building it myself. That’s how Cuéntamo was born.
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The Lice Conspiracy: Someone Had to Do the Math
Could pharmaceutical companies deliberately spread head lice to boost shampoo sales? Probably not. But after examining the biology, logistics, economics, and available evidence, I found the question far more technically plausible than the usual dismissals suggest. Sometimes the interesting part is not the conclusion, but the numbers.
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UI tests are the guardrails an AI needs: the story of clipboardwire
I built clipboardwire to synchronize the clipboard between Linux (Wayland) and Windows. After rejecting existing alternatives, I designed the architecture and security model while Claude Code wrote the implementation. Automated tests, including GUI tests, enabled safe iteration without regressions. The result is a lightweight, open-source utility.
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Smart Misting in My Patio Garden – with Home Assistant Automation
I built a Home Assistant automation that controls a patio misting system based on temperature, humidity, and wind. Instead of running continuously, it dynamically adjusts misting duration and cycle frequency to maximize cooling while minimizing water use. The blueprint is open, reusable, and easily customizable.
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Bad News: My Qvadis smart intercom and door opener is becoming dumb
Qvadis shutting down its cloud servers turns a fully functional smart intercom into a severely limited device. This article explores the risks of relying on proprietary cloud services and argues for open, documented solutions that let users maintain, integrate, and control the hardware they already own.
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Home Lighting Automation: Smart Relays with Home Assistant
In my home automation project, one of my first goals was to control all the lighting. From being able to turn off all the lights that my kids (who act like they own Iberdrola) insist on leaving on, to turning off the kitchen light when leaving with my hands full. And also, why not — because it’s just cool to…
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My AJAX alarm completely integrated into Home Assistant
As I mentioned a few weeks ago in my post Prosegur Alarms: A Step Back in Home Assistant Integration, I’ve installed an AJAX alarm system at home. And despite some voices claiming it wasn’t possible, I now have it successfully connected both to an Alarm Receiving Center (ARC) and to my Home Assistant home automation hub. This integration allows me…
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Prosegur Alarms: A Step Back in Home Assistant Integration
In the world of home automation, integration between devices and services is key to ensuring a seamless and convenient experience. That’s why I always appreciate it when a service provider or manufacturer facilitates access to their API, allowing the community (or the company itself) to develop integrations for platforms like Home Assistant. Unfortunately, this support is not always maintained, and…
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Home Assistant: My Laundry Room Automations
At home, we have our washing machine and tumble dryier in the laundry room in the attic. When the attic door is closed it’s really difficult for us realizing when the washing machine and/or the tumble dryer have finished the corresponding washing/drying cycles. Because of this, taking advantage of the home automation system based on Home Assistant, I’ve built a…