Jeantje is a 49-year old IT professional who is working in the security field for many years and who has a broad knowledge about reversing and counter measurements. She is the author of a well-known program to protect files against reversing. Jeantje is also the author of different materials and writings, freeware programs and tools. Jeantje knows what she is talking about. Proof is that she wrote a program on which she challenged the reversing community to break its protection. Although she mentioned most tricks it uses and provided registration keys for it herself ... it has not yet been broken since till date!

appsec.ch is run by people working in the security field. They mainly focus on application and operating system security and have experience in penetration testing, IT audits, incident response and malware analysis. One of their members published a book about hacking techniques and defense mechanisms that is being sold on amazon. Movies provided by appsec.ch cover various topics in the security field, ranging from finding and exploiting software vulnerabilities in Windows, Linux and Mac OS X to tools and techniques used during security assessments/penetration tests.