Show HN: PlugBrain block distracting apps with math challenges

PlugBrain began as a personal tool I built to manage screen time for myself and my loved ones. Later, I shared the source code with a group of students as a teaching project, showing them how real-world app development works: from development, writing tests, to setting up CI/CD automation, to collaborating on an open source project. What started as a personal experiment and a learning exercise eventually grew into something bigger, and today PlugBrain is fully open source.