Contact me

My name is Kuba Gretzky (aka Jakub Udymowski-Grecki). I've been working in the cybersecurity industry for more than 10 years. Offensive security software development is my passion. In recent years I've developed several private and open-source security tools recognized by major red teaming companies worldwide.

Feel free to contact me on Twitter @mrgretzky, send me an e-mail at or connect via LinkedIn.

I want to work with passionate and skilled people who treat security seriously. My skills can help companies with vulnerability research and offensive tool development.

In my free time, I do security research and run a security blog, where I post about my research or new tool releases. I've been a speaker at hacking conferences where I presented my work.

I also do consulting and phishing simulations using my reverse proxy tools to demonstrate the weaknesses of multi-factor authentication.

My background is in game hacking, which involves a lot of reverse engineering, vulnerability research and software development. That's how I trained most of the skills I'm now using in cybersecurity.

If you need a passionate security researcher and software developer, do reach out and let me know what you need.

I am the creator of:

  • Evilginx reverse-proxy phishing framework
  • pwndrop self-deployable file hosting service for red teams
  • BREAKDEV security blog

I am the founder of Breakpoint Software Development company, which has been on the market since 2008. The company provides the following services:

Offensive Tools Development

If your company runs a red team and/or develops red teaming tools in-house, my skills and expertise can help you with:

  • Evading AV & EDR detection of your payloads
  • Simulating reverse-proxy phishing scenarios
  • Infection payload development
  • C2 and agent development
  • Shellcode development with obfuscation

Phishing Simulations & Consulting

I can prepare a phishing simulation for your company, analyze your company's weaknesses and educate your employees on how attackers work and what they should look out for.

  • One or two-week phishing attack simulation targeting company employees
  • Detailed report on phishing engagement results
  • Feedback report on how the security of the company can be improved to protect against phishing attacks

Educational Courses in Cybersecurity

I am sharing my knowledge through offline video courses in cybersecurity. If you are interested in learning cybersecurity, here is the list of courses my company provides:

  • Evilginx Mastery - Learn everything about the latest methods of phishing, using reverse proxying to bypass Multi-Factor Authentication. Learn to think like an attacker, during your red team engagements, and become the master of phishing with Evilginx.

How to contact me:

Company details:

Breakpoint Software Development
Wzgórze Bernadowo 75B/1
81-583 Gdynia, Poland
VAT ID: PL5862225188