• Over 7 years of industry Web development experience in an Agile/Scrum environment. • Hands-on experience in developing and maintaining Android SDK, Services and apps to support multiple Android devices with different versions of Android and Google Play Services. • Strong experience in doing development with service-oriented architecture (SOA); skilled in building complex distributed applications leveraging Web Service technologies, such as Amazon S3 and Elastic Map Reduce. • Years of ownership of online services; solid understanding of building robust and maintainable large scale systems.

Software Engineer @ Android Wear (05/2014 - Present) Core developer of Android Wear service framework, which connects wearables to other Android devices, and provides Android Wear SDK to app developers. Technologies: Android, Java, Google Play Services, Protocol Buffers, Spanner, Blobstore, JSON Google Shopping Express (05/2013- 05/2014) Drove growth by expanding shopping express to new areas and product lines, with more shipping options. • Worked closely with PMs on product requirements and constraints introduced by regulations, product or locale specific restrictions (e.g. for Perishables and Alcohol), and came up with proper technical design for expansion. • Led the implementation, including inventory and catalog management, indexing and serving, and search client. Technologies: BigTable, Colossus, MapReduce, Mustang(indexing and serving), Protocol Buffers, Java, Javascript, C++ From May 2013 to Present (2 years 8 months) Software Engineer @ Key developer of Amazon product defect detection system, whose outputs were consumed by product search to refine search results and were published to millions of 3rd party sellers to improve online product data and to help sales: • A fully distributed application processing 40 billion records per build with 16 input sources and 3 output targets, over 200 steps synchronized using Amazon Simple Workflow Service (SWF). • An Elastic Map Reduce (EMR) cluster of 350 hosts was used for production build. • Integrated with SABLE, an internal high available and scalable NoSQL storage and pre-computation service. Technologies: Java, S3, EC2, Hadoop, Elastic Map Reduce (EMR), SimpleDB, Simple Workflow Service (SWF) Designed and implemented a general purpose Web Service for catalog management: • Owned the full life cycle of creating a scalable Web Service for updating Amazon catalog, hiding all the underlying complexities of interacting with various heterogeneous services. • Integrated Amazon smart reconciliation engine and brand normalization engine with the service. Technologies: Java, Amazon Service Framework, SOA, Jetty, REST, SOAP, XML, Oracle Created a community based product improving system: • Owned it from the front end to backend processing and the Admin tool. • Auto approval engine has been gradually enhanced from a manually tuned naive model to a random forest based machine learning model. Technologies: Java, Javascript, HTML, CSS, Tomcat, Hibernate, Oracle, Simple Queue, Random Forest From December 2007 to May 2013 (5 years 6 months) Research Assistant @ • Increased the performance of a parallel Cholesky decomposition algorithm by 30 percent by utilizing Z-order matrix storage, which can fit into every level of a memory hierarchy to benefit from data locality. Technologies: C/C++, Message Passing Interface (MPI), Linux Cluster (128 hosts) From June 2005 to June 2007 (2 years 1 month)

Jeff Deng is skilled in: Java, Hadoop, Web Services, Distributed Systems, REST, Scalability, Algorithms, MapReduce, Linux, C++, SOA, Amazon Web Services (AWS), Object Oriented Design, XML, JavaScript