We already know that Microsoft, Amazon, and Zillow made multimillion-dollar donations to help build a new University of Washington computer science and engineering building. But another tech giant has also contributed to the expansion — albeit in a quieter way.

Google confirmed to GeekWire today that it is donating $10 million to the University of Washington. The gift is “a mix of support for research projects and research facilities,” according to a new mention on the UW website for the second computer science building, which counts Google’s donation among the $90 million in commitments raised for the project as of this month.

The 135,000 square-foot building will double the capacity of the university’s top-rated CSE program and allow the department to award more than 600 degrees annually. Google, based in Mountain View, Calif., has been dramatically expanding its presence in the Seattle area, and the UW is a top source of engineering talent for tech companies in the region.

Google’s donation is part of an ongoing collaboration with the UW as a research partner — the UW is one of the top programs in receipt of quarterly Google faculty research awards and Google graduate fellowships — and a sign of Google’s support for academia and computer science. The funds are intended to support exploratory research and facilities, and aren’t restricted to any specific focus.

While Microsoft, Amazon, and Zillow are all based in the Seattle region, Google and its parent company Alphabet are headquartered in Silicon Valley. But Google has had a presence in the Seattle area since 2004, when it was one of the original Bay Area tech giants to establish an engineering center in the Seattle region.

In the decade since the current UW CSE building opened, the demand for computer science graduates has skyrocketed in the Seattle region, thanks to a strong startup ecosystem, Amazon’s rapid growth, and the opening of Seattle-area engineering offices by Google, Facebook, and many other tech companies based outside the region.

Google’s Kirkland engineering office expanded last year and now totals 375,000 square feet, housing more than 1,000 people who work on products like Google+, Cloud, and Chrome. Google also employs hundreds more at offices in Bothell and Seattle’s Fremont neighborhood, and it’s planning to move its Seattle operations to a large new project in the South Lake Union area.

Google’s commitment is a clear statement about their role as a full partner in the Seattle tech community.

The estimated project cost for the new CSE building is $105.5 million. Google, Microsoft and Amazon have each committed $10 million, and Zillow has donated $5 million. The state is putting in $17.5 million, with the rest coming from various university funds and individual contributors.

“We’re thrilled with the support we’ve received from Microsoft, Amazon, Zillow, Google, and more than 100 friends and alumni,” said Ed Lazowska, Bill & Melinda Gates chair in the UW CSE department. “Thanks to them, diesel excavators are hard at work, and we’ll have the space to double our enrollment. Google’s commitment is a clear statement about their role as a full partner in the Seattle tech community.”

The UW Board of Regents officially approved the funding and budget plan last month and construction has already started. Completion is expected by December 2018. The new building will include 16 labs, a lecture hall, two classrooms, three seminar rooms, an event space, communal and study spaces, office and support spaces.

Last year, CSE became the leading “first-choice” major among confirmed incoming UW freshmen, surpassing the longtime leading preferred major, Business Administration. UW says it currently has to turn away two out of every three qualified student applicants in the CSE department.