William George Stanley, 78, of Concord, passed away at Concord Park on April 19, 2021. Bill was born in Winchester as the son of the late Betty and Lou Stanley, and grew up in North Beverly. Bill was a software pioneer. Trained as physicist with a BS from RPI and an MS, PHD from Boston College, he fell in love with computers while working at Lincoln Labs in graduate school. He spent his professional life as a solids modeling software developer – first at Computervision in the early days, through a variety of startups, and retired as a Technical Fellow from Parametric Technology. In retirement, he designed and set up science experiments in the Lowell Public Schools. Bill loved road trips, the ocean, hot chocolate and mint chocolate chip ice cream ("Grampy's ice cream"). He climbed Mount Katahdin and Mount Washington every year when he was able, and for years organized a New Year's Day plunge into the frigid waters of Good Harbor Beach in Gloucester. He was a good man who did his best to support his family and community. He leaves his devoted wife of 54 years, Marian McMahon Stanley, four wonderful children, Maggie Stanley of Concord, Nick Stanley and his wife Solita of British Columbia, Katherine Wilson and her husband Stephen of Concord and Mary Ahmad and her husband Daanish of Sudbury, as well as seven cherished grandchildren - Josie, Desmond, Johanna, Peter, Damian, Nolan and Molly and steadfast canine pal Archie. Bill also leaves his sister Ellen Eaton of Topsfield, brother Robert Stanley and his wife Kathleen of Bridgeport, CT, and sisters and brothers-in-law, Jane Compagnone of Pittsburgh, Gerald and Joanne McMahon of Ipswich, Robert and Sandra McMahon of Saugus, as well as many well-loved nieces, nephews, cousins and friends. In addition to his parents, he is predeceased by his sister Natalie Moxcey, and brothers-in-law, Ralph Compagnone, Thomas Eaton, Thomas McMahon and Richard Moxcey. Relatives and friends are invited to celebrate Bill's life during visiting hours on Tuesday, April 27th from 3 to 6 pm in the Dee Funeral Home, 27 Bedford Street, Concord Center. A funeral procession will form at the Dee Funeral Home on Wednesday, April 28th at 10:45 am, followed by a graveside service in The Knoll section of Sleepy Hollow Cemetery at 11 am. A memorial service will be planned for the summer. In lieu of flowers, donations in Bill's memory may be made to the National Center for Race Amity , 100 Powder Mill Road, Suite 245, Acton 01720 or The Union of Concerned Scientists , 2 Brattle Street, Cambridge, MA 02138. Arrangements are under the care of Dee Funeral Home & Cremation Service of Concord.