Currently working as senior database engineer in Allegro.pl. I started my career as a C later Java and Perl programmer in 2001 then I started working with relational databases as database developer and admin mainly with Oracle. I worked for GSK as senior Oracle admin and system architect 2007-2010. Since 2011 I work for Allegro.pl a senior database engineer. We have multiple Oracle, Postgres and MySQL clusters as well as various NoSQL data stores. Allegro.pl is an online web marketplace operating mainly in Poland. We have 20M users.