I joined the AdMob engineering and operations group a little over 10 months ago. Even though it doesn’t seem like a lot of time, the fact is that our team, the products that we build, and the systems that we operate have all changed dramatically in the past 10 months.

First of all, AdMob engineering has doubled in size and now accounts for more than half of AdMob’s employees worldwide. We’ve had the good fortune of hiring great engineers from all over the country. Technical AdMobsters have diverse professional backgrounds including high-performance distributed systems, machine learning, optimization, statistics, physics, networking, database server engineering, signal processing, tera-scale data-warehousing, philosophy, application and UI engineering, security, and compiler optimization.

Second, almost every aspect of AdMob’s business has grown by leaps and bounds over the past 10 months. For instance, when I joined in July 2007 we had our first 1 billion ad month. As I write this post, we are on track to serve 3 billion ads in May 2008. One of our biggest engineering challenges has been designing and implementing ad serving systems that can scale to handle this rapidly-growing traffic. Due to the hard work and talent of our engineers, AdMob’s systems are substantially faster and more reliable at 3 billion ads per month than they were at 1 billion ads per month. In addition to building capacity and improving performance domestically, we’ve made ad serving faster for the substantial portion of traffic that originates outside of the US by locating serving infrastructure abroad. We can now cost-effectively increase our worldwide ad serving capacity to handle many doublings of traffic by adding cheap, commodity hardware to our serving clusters.

Third, AdMob engineering is investing heavily in the research and engineering work required to optimize how ads in our network are allocated. A couple of thousand times per second our ad servers must decide which ad is ‘best’ suited to be shown to a given user browsing a given site in our network. Our system considers a large number of factors when making ad allocation decisions. For each of these decisions, we look at budgeting and targeting constraints for thousands of ads, historical data about how ads perform in a variety of different contexts, and information about the specific context in which the ad has been requested. These new optimization systems are producing rather positive results for advertisers, sites which run AdMob ads, and the users of those sites.

Fourth, AdMob engineering has increased the rate at which we’re creating and improving products. In the month of May alone we’ve added the ability for performance advertisers to add an image to be served with their text ads, we’ve substantially improved the user interface for creating and editing ads, and we’ve launched a mobile analytics product into private beta. In addition to these easily-visible projects, 3 to 4 times per week we ship incremental improvements to our systems as part of our ongoing efforts to make our systems faster, our products easier to use, and to ensure that AdMob technology is yielding better results for customers and the mobile ecosystem at large.

Finally, as exciting as the last 10 months have been and as proud as I am of the technology that we’ve already built, there is more excitement to be had and much more interesting technology to be built in the months and years to come. So if you’re an engineer / statistician / applied mathematician / hacker extraordinaire, we are hiring right now for all positions. I can promise that our problems are challenging, that your colleagues will be incredibly smart and passionate about their work, and that you’ll have the ability to impact millions of users throughout the world.

–Kevin Scott