In network and application security since mid-90's. Done quite a lot of different things, starting from low-level penetration testing, embedded devices design, EU electronic signature consulting and large scale application security management. Active member of OWASP. Author of WebCookies.info and CSPBuilder.info. Writing at two blogs: IPSec.pl (English/Polish) and Echelon.pl (Polish only).
Q&A for professional and enthusiast programmers
Q&A for information security professionals
Q&A for pro webmasters
Q&A for software developers, mathematicians and others interested in cryptography
Q&A for enthusiasts and power users of the Android operating system
Q&A for system and network administrators
Q&A for users of Linux, FreeBSD and other Un*x-like operating systems