Hi, I’m Marijan Batarilo

I build systems, then break them.

Over seven years of production backends, e-commerce platforms, cloud infrastructure (GCP), systems under real load. Now doing application security on the same kinds of systems I used to build. A lot of the code shipping today is AI-generated, and it ships fast and breaks worse.

This site is the permanent home for everything I make and write, case studies from real projects, security writeups, learnings and tooling.

Currently

  • Building and running e-commerce stores for clients (Shopify, BigCommerce, Hydrogen, GCP, Vercel). Mostly working with Next.js, Go and Python for data stuff
  • Studying cyber security daily - at the moment appsec, working through PortSwigger labs toward the Burp Suite Certified Practitioner exam, starting web bug bounty hunting for practice and exploring cyber security to mastery
  • Contributing to open-source software, my GitHub
  • Documenting my journey on social media
  • Engineering my AI agent harness and automation tooling as a force multiplier for everything above

And if you’re wondering if AI will replace you: “Fear is only for the weak. And I… am no longer weak.” – Jin-Woo