About PrepaJS
PrepaJS started as a personal collection of notes—a way for me to document my journey mastering the intricacies of JavaScript.
Why this exists
During my preparation for senior engineering roles, I realized that while there are many tutorials, few resources offer deeply interactive, bite-sized "notebooks" that let you visualize concepts immediately. I wanted to change that.
Every notebook and quiz here is handcrafted based on real interview scenarios and common pitfalls I've encountered in my career.
Our Mission
To provide high-quality, free, and accessible resources for developers worldwide. Whether you're preparing for a FAANG interview or just brushing up on ES6+ features, PrepaJS is designed to be your quick-reference companion.
Transparency & Quality
We believe in learning by doing. That's why every topic comes with an interactive notebook and a challenging quiz. We are committed to keeping this content free, supported by non-intrusive advertising.