Software executive David Duffield has listed his pet-friendly 21.48-acre estate in Alamo, California, for $39 million.

Duffield and his wife, Cheryl, will donate the proceeds of the sale to Maddie’s Fund, a nonprofit animal welfare charity that the Duffields began in 1994 in memory of their dog, Maddie, who passed away in 1997.

The massive compound, which features a soundproof aviary, a dog spa, and a dog park, is located at the base of Mount Diablo, about 30 miles from San Francisco. The estate also holds a 20,467-square-foot main house designed in the fashion of an English manor that features stone walls and reclaimed wood beams.

The acreage includes amenities like a swimming pool, a plunge pool with a water slide, a lounge with a private theater, and a 75-foot suspension bridge that leads to a tree house.

The Duffields, who have 10 children, moved back to Lake Tahoe, which they left in 2005 so Mr. Duffield could be closer to his offices at Workday, where he is co-founder and Chairman. Duffield also was a founder of PeopleSoft, an HR management software firm that sold in 2005.

To date, the Duffields have benefited over $300 million to Maddie’s Fund, which helps save the lives of pets across the United States with adoptions and by providing no-kill shelters with funding.

Photo credit: Thomas Grubba and Open Homes Photography