More than 15 years experience with *nix based systems. Started with IBM AIX and SUN Solaris mainframes, later moved to *BSD and Linux. In depth knowledge of Linux (driver programming). In depth knowledge of of Samba, Postfix and Dovecot (familiar with sources, some of my patches/code included in releases). God knowledge of most well known applications like Apache, OpenLDAP etc. Experienced in high load (100 000+ active users) server/cluster maintenance.