Hello! You've landed at a page that used to be the DEF CON Capture-the-Flag qualifiers. This particular contest ended several years ago; our running of the contest went from 2013 to 2017.
If you're looking for information from DEF CON CTF from those years:
(These organizations are not responsible for maintaining this site)
If you have any questions about this, please ask Vito (firstname.lastname@example.org).