Monthly Archives: January 1970


You can contact me by e-mail via sijmen(a), by phone and Signal 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: 2017-01-31 Websites Nederlandse politieke … 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 2017-06-19 Communications Security Establishment ‘CSE Cyber Threat Assessment’ 2017-06-16 Radio interview: ‘Brits defensiebedrijf verkoopt spionagesoftware’ 2017-05-15 … Continue reading

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

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Quite often journalists ask me to send photo’s. To speed things up I’ve collected some so I can easily reference them to this page: International news agency AFP has put up a stock video on GettyImages about my election hacking … Continue reading

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