Our infrastructure is designed to provide the most scalable and flexible environment possible. We operate out of two data centres, and have a platform that allows us to easily move load between these two sites. This provides a redundant infrastructure, and allows the majority of maintenance to be done during the day, without impacting our sites.
We run a distributed database architecture, allowing us to share the massive amounts of transactions over numerous servers and database instances. We are predominantly a Microsoft shop, but have a smattering of other technologies around as well. Our core database servers are clustered, providing even further redundancy.
Our network is a mix of F5 and Cisco (and cables), handling oodles of traffic and connections. On any given day we can send as much as 6TB of data out to the Internet and send over 2.5 million emails.
Our web server platform is based on commodity blade hardware allowing us to scale out quickly and affordably. Our network platform balances all load equally over our web servers at both data centres. Our image servers hold up to 300 million live images at any given time. These images are heavily requested and we serve them from memory using a product called Varnish, running on commodity hardware.
We develop our sites primarily in ASP.NET using C#, Visual Basic and Mercurial source control.