The scale of the challenge facing Agents’ Mutual should not be under-estimated – if an interview with Rightmove’s head of operations, Tim Harding, is anything to go by.

In the interview, he reveals that out of the 400 current staff, 69 are IT developers.

He also reveals that Rightmove pays external consultants to try to hack into it.

It’s interesting stuff! The full interview is below.

How many people are involved in the running of the website?

A total of 400 people now work at Rightmove. There are 12 people in my team and 69 developers. Put very simply, we’re the people who make sure the site works, that it’s secure and that it’s performing as it should be. We also take new applications and features that the developers create, such as Real-time Data Feed and Sold Prices on mobile, and put them into production so that they do what they’ve been designed to.

So essentially we do all the things behind the scenes that people don’t see, to make sure that what they see or do on the site is what they expect.

My team’s doubled in size since the start of 2012 and we’ve got people on call 24/7, 365 days a year, even on Christmas Day when we’ve been getting more and more visitors every year.

What are the big challenges that come with running a website that serves up 45 million page views a day?

First, there’s the need to be super quick. If we spot an issue, especially one that might have a number of different causes, we need to know what to do straight away to fix it. So we’ve invested in experienced and knowledgeable staff, who are always ready to expect the unexpected.

To safeguard the site we check for issues in thousands of different ways, and to keep the site secure we have regular penetration testing by external consultants, which in effect means we pay people to try and hack into the site and report back to us.

We send over 50,000 email leads a day to customers and over one million property alerts to consumers, which equals a vast amount of data going through our mail server.

If we have a new feature that really takes off with consumers, like the recent newly designed property alerts, we need to have already thought about the effect the increase in emails being sent will have.

What additional challenges have come with new platforms such as mobile and apps?

One of the big changes we’ve noticed as more people use Rightmove on mobile (through apps and the mobile website) is that our daily traffic patterns have changed and we now have an extra peak in the evening as people use their phones and tables whilst travelling home from work.

As well as the peak times, we also know that people use the site in the middle of the night, perhaps if they can’t sleep, or if it’s the only time they can get some peace and quiet to look for a new home.

Differences in things like reliable network connectivity and available bandwidth – as well as obvious things like screen size – for mobile devices mean that both the mobile site and the infrastructure we use to serve are optimised differently than for the desktop website.

How do you and your team make sure the site is always up and working well?

Having 1.6m people visit the site daily, and being one of the UK’s busiest websites alongside Google and Amazon, means that people have very high expectations. When they type in Rightmove they expect it to work, and to work fast.

To maintain 99.99% availability we need a lot of infrastructure. For example, we have 250 physical servers and three separate data centres that we control in various different locations, which have multiple power supplies and back-up network connections.

So in the unlikely event that there was a power cut in all three of our data centres at the same time, the site could still run as normal thanks to back-up generators.

Everything is controlled by Rightmove, not external companies, to ensure it’s to the high standard that we and our customers expect.

It’s also part of our job to monitor for spikes in demand so something like the purple house going viral last year may have been good news for our marketing team but potentially not such good news for us! Luckily once again we were prepared for that big influx of traffic.

How much data is there and how can agents use it?

Since we launched nearly 15 years ago there have been nearly 40 million properties listed on the site, with almost 3 billion images.

At any one time there are over 1 million properties on Rightmove, and on average 1.5 million images are uploaded daily, which averages 1,000 images per minute.

There’s lots of other data that our customers can make use of in Rightmove Plus, and we’re currently making enhancements to these tools for the new Rightmove Intel, which will provide improved ways for our customers to measure market share and benchmark against competitors.