Category Archives: menu


You can contact me by e-mail via sijmen(a), by phone and Signal (most secure option) via +31652627625, or via the contact form below:

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Almost all my professional work is highly confidential and thus I cannot publicize about it. Sometimes I find time in my busy work schedule to write about some of my research which doesn’t fall under a non disclosure agreement: 2017-09-29 One of the … Continue reading

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About me

For over more than 19 years I’m an aficionado for anything related to internet security and developing secure software. I’m specialized in hacking, IT security research and performing advanced penetration testing. My specialty is breaking IT security and then explaining … Continue reading

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In the media

Sometimes the media talks or interviews me about my work, and sometimes I get the opportunity to speak at events: Date Website Subject 2017-11-15 ‘Minister pakt Russische site met privédocumenten van Nederlanders niet aan’ 2017-11-14 Ellen Timmer ‘Russische IT-ondernemer … Continue reading

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My company: Secundity My resume: LinkedIn My short updates: Twitter My presentations: SlideShare

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The following events are public were I take part in: Name Date Subject Cyber Security Congres 2017 2017-11-22 Presentation: ‘Hoe onze verkiezingen de afgelopen 26 jaar gehackt konden worden?’

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