The former Stevenage manager is the Gloves new boss, the club have tonight confirmed.
He signs a three-year deal and straight away begins the job of preparing a squad ready to challenge for promotion back to League Two.
The club were relegated in May alongside Notts County and a new chapter has now begun at Huish Park.
"I am proud and honoured to be leading this club in its next journey," he said. "We have to accept where we are, get back up and be proud of our club."
The 36-year-old’s arrival has been a while coming but chairman John Fry believes they have the right man.
“Darren’s appointment has been made with the full backing of the new owners and a further announcement on this will be made shortly, once we have received approval from the National League,” he said on the club’s website.
“I would like to thank all Glovers supporters, staff and players for their patience whilst the search for a new manager has been carried out.”