Derry have moved top of the Airtricity Premier Division after a comfortable win over the basement club at Terryland Park on Friday night.
Eamon Zayed put a dominant City ahead on 11 minutes from a penalty after a foul on Sean Friars.
The striker netted again after 39 minutes with a close-range header from Patrick McEleney's cross.
The pair combined for the third, with McEleney firing into the bottom corner in the 75th minute.
Derry lead the standings on goal difference from Shamrock Rovers, who defeated Bohemians 1-0.
Drogheda United earned a 2-1 victory at Bray Wanderers in Friday night's other Premier Division game.