Hello there!

My name is Nemesis Contreras. I’m a Senior Application Security Engineer with 7 years of experience. I’ve worked across various industries, such as healthcare, financial services, cybersecurity, and embedded systems. I enjoy working in ambiguous spaces, challenging assumptions, and learning things outside of my immediate discipline!

I’m a curious person by nature. I like to build things, break things, and understand how they work as a whole. I approach security as a systems problem. Zooming out to understand the users, business goals, and assumptions surrounding an issue to make better decisions.

Some things I like to chatter about:

• Modern Security for web applications and mobile applications
• Why the new generation of security teams should build, automate, and fix
• Emotional intelligence as taught by Marc Brackett, director of the Yale Center for Emotional Intelligence, and why it’s so critical for engineers
• Hayao Miyazaki films and all the little lessons they carry about resilience, humanity, and becoming a better person

Some fun things I did in the past:

• Wrote an RCE proof of concept for CVE-2025-55182 and CVE-2025-66478, the React2Shell vulnerability writeup here.
• Gave back to my community by teaching students at MLK Middle School in Berkeley how to hack Android applications! Video here
• Had CTF tweets go viral on X/Twitter, grew my community Discord server to 3,000+ users, and eventually had HackerOne acquire my server! Fun fact it’s their official H1 Discord server to this day well over 80k users now!
• Published hardware tutorials on Instructables that have over 550,000 views and earned a bronze medal.