Englishman Rooney (35) officially led the club in only two matches: a 1-1 draw in the Irish Premiership with Cliftonville at Inver Park and a 5-0 BetMcLean Cup win against Annagh United.
Rooney’s assistant Haveron was responsible for Larne’s Conference League defeats to Olimpija and Dinamo Minsk.
Haveron spent three years as Carrick’s manager but spent just 17 months at Glens before joining former boss Lynch’s coaching staff in April 2023.
His first match as official head coach will be Larne’s final Conference League match at home to Gent on Thursday evening.
Larne also confirmed that former midfielder Andy Mitchell has left his role as technical director of youth to “take up a senior coaching role elsewhere”.
“He has worked tirelessly to create a number of structures below first-team level that will enable us to continue to develop,” Curneen said of Mitchell.
“Our academy and scholarship program are a huge part of our plans and will continue to be.
“Our previous manager Tiernan Lynch served as both manager and head of football operations and Nathan will take on this role as head of football.”
Next up Larne will face Belgian side Gent in their final Conference League match on Thursday evening.
