Senior Software Engineer of Data Science

AppNexus is an internet technology company that enables and optimizes the real-time sale and purchase of digital advertising. Our powerful, real-time decisioning platform supports core products that enable publishers to maximize yield; and marketers and agencies to harness data and machine learning to deliver intelligent and customized campaigns. Headquartered in New York City, AppNexus employs over 1000 professionals in offices spanning five continents.

**Consider some of the problems you will try to solve:** * **Conversion attribution:** In online advertising, we have to figure out which events caused a particular conversion – or which ad impression caused a user to make a purchase. We hunt for the needle in a 150 billion-row "haystack," and we do this millions of times every hour. We then use this to infer why the conversion happened and how we can change our real-time buying strategy to achieve more of these. * **Processing data fast and reliably:** Our team is processing more and more data, pushing our decision engines to run with as little latency as possible. We get a kick out of making things that once took hours, only take minutes. * **Scale:** We are always seeking new and better ideas to help us meet our challenges. Our engineers get to build Internet-scale solutions to solve interesting math problems. **About the job:** * Design and develop large scale, high-performance software that interfaces multiple components of the AppNexus stack in order to identify and analyze new quantitative solutions in an effort to optimize our Clients' day-to-day businesses * Collaborate with Data Scientists to create and implement complex mathematical models and other automated/algorithmic solutions out into production * Work closely with other engineering teams to realize and implement the next evolution of our analytics driven software – building real-time decision making engines into the core business-generating aspects of the platform * Design/Implement/test and deploy code to production * Maintain and improve our code quality and stability * Provide mentorship * Implement technology frameworks * Act as a tech lead for projects

**About your skills:** * BA/BS degree and 6+ years of experience OR MS degree and 2+ years of experience in software engineering (Degree in Computer Science or related field preferred) * Strong knowledge of Java, Python, or C++ * Mathematically literate * Experience with Map/Reduce, batch processing such as Hadoop * Experience with Stream based passed processing models; experience with Storm or Spark a big plus * Experience with NoSQL, MySQL **More about you:** * You are passionate about a culture of learning and teaching. You love challenging yourself to constantly improve, and sharing your knowledge to empower others * You like to take risks when looking for novel solutions to complex problems. If faced with roadblocks, you continue to reach higher to make greatness happen * You care about solving big, systemic problems. You look beyond the surface to understand root causes so that you can build long-term solutions for the whole ecosystem * You believe in not only serving customers, but also empowering them by providing knowledge and tools