Amazon is expanding its footprint in the Bay State, adding a 350,000-square-foot Westboro outpost that houses corporate offices, research and development labs, and a robotics manufacturing space. "This new innovation and manufacturing hub, along with its sister site up in North Reading, places Amazon robotics at the epicenter of robotics innovation here in Massachusetts for years to come," said Scott Dresser, vice president of robotics at Amazon. The site, once home to drugmaker AstraZeneca, has been open for a few months and was buzzing with activity Thursday afternoon during the official ribbon-cutting for the site, with Lt. Gov. Karyn Polito and Housing and Economic Development Secretary Mike Kennealy in attendance. Amazon began introducing robots into its facilities in 2012, and since then, has also added over a million employees to work alongside the more than 350,000 robots. Though Amazon Robotics has had a North Reading site for about 10 years, which hosts similar roles to the Westboro facility, the new one "is the first in terms of size and scale of operations for Amazon Robotics," according to an Amazon spokesperson.