Zopa - What’s Inside ?

Posted by Tim at 2:37 pm

I look after the IT for Zopa. At the moment, I spend about 90% of my time on Zopa and the other 10% on helping-out a couple of other clients.

Sarah and Dave just reminded me about this new blog, so I thought I’d share some of the details about how, who and what makes Zopa tick (technically speaking) …

I’ll start with what we have now.

We have our servers tucked-away in the corner of a very large datacentre in London run by a company called Level3. (They run a huge chunk of the internet). I’ve only been in the datacentre once (a sort of state visit to see the boxes). The security is second only to that of the Swiss banks (one of my ex-clients designed their datacentre to withstand a direct nuclear hit …). We don’t go that far, but we do have our servers sitting behind many layers of firewalls and a full set of servers just sitting in an office on standby, just in case ….

We run .NET on a series of Dell servers around a MS SQL Server database.

A company called Magex manage the servers and network for us. They have a small and dedicated team of technical infrastructure specialists who install the kit, keep the network connections running, manage the firewalls and generally keep a close eye on all the Zopa infrastructure. They monitor it 24*7 so that I can get some sleep. The environment is very secure, and since we want to keep it that way, I won’t tell you much more about it.

Our application is quite complex. At the heart is the “matching engine”: a sleek bit of code designed and coded by Ian, our chief developer. (I would ask Ian if he’d like to put something up here, but chances are he’d prefer to improve the matching engine instead…).

Supporting the matching engine, and all the screens, is something we call “the cradle”. This manages all the database interactions and ensures that every transaction is authorised, and is completed fully, or not at all. It also logs every single update ever made to the database … which gives us a full audit trail of everything. All the other code nestles inside the cradle …

Ian and his colleagues work for a development company in Leeds called BJSS. They specialise in high-performance mission-critical systems and have done lots of work with City trading systems and a slew of Big Name IT firms … We don’t call it “near-shore development”, but I suppose that’s effectively what it is.

As well as the active parts of the website, we have quite a few other pages: the one’s which describe who we are, Contact Us, the Markeplace display, Help, and how to Lend and Borrow. These were built by a small agency (Pynk and Fluffy .. who aren’t pink and aren’t fluffy) and are now maintained by our current digital agency Harvest (as well as ourselves: we regularly update the wording…the easy bits anyway).

About once a week we do an upgrade. It’s been a bit quieter over the summer, but that’ll stop soon. We’re embarking on a lot of new changes and we’ll soon be back to the weekly “down for maintenance” page. We try really hard to keep these releases short, so that it has limited impact on users - normally about 30 minutes. Not all releases mean the site has to come down: only those which change the database.

Oh, and about me: I’m old enough to have coded in COBOL & to wonder if an upstart called Microsoft would ever make it big ….. I’ve worked in the finance sector for much of my career, including many of the big finance houses and Egg (where I met Richard & what led me to Zopa).

It’s been great fun getting Zopa off the ground, taking a great idea and a Powerpoint presentation and turning it into something we can all use.

Next time I’ll post up something about ‘How we built Zopa’. The time after that I could post something about Zopa’s MI and Risk Management. We have some tricky stuff running behind the scenes.

Meantime, feel free to post any comments.

Right now, I’d better get back to work. I need to design and arrange the next release …

Tim

This entry was posted on Wednesday, September 14th, 2005 at 2:37 pm and is filed under Team, Technology. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.