The Warriors and long-time assistant coach Ron Adams agreed in principle to a contract on Sunday night, the team confirmed.
He is the second coach to join Steve Kerr's staff, as Alvin Gentry will be the team's associate head coach.
Adams, 67, served as an assistant to Brad Stevens with the Celtics last season.
He spent the previous three seasons with Tom Thibodeau in Chicago, and was an assistant for Oklahoma City for the 2009 and 2010 seasons.
Adams also served as an assistant for the San Antonio Spurs, Philadelphia 76ers and Milwaukee Bucks.