Tarek has been working on Bookings.com’s hotel availability and its core reservation platforms since he joined back in October 2014. This exposed a lot of opportunities to work with different databases for different needs of both platforms. Understanding along the way how one systems preferences is another system’s death note.Tarek currently writes a lot of Java and Perl at Booking.com. During his time at Booking.com Tarek left intermittently to join Yelp where he worked on their realtime metrics systems dealing with different Time-Series databases. This opportunity caused a lot of interaction with software such as Cassandra and Graphite. During his time at Yelp, Tarek was also one of the core maintainers of Yelp’s open source system metrics collection tool, name “fullerite”, which can be found on GitHub. Since March 2016, however Tarek has been back working at Booking.com.