LYNN – When she went to work as a City Hall secretary, Judith Lewin-Callahan thought she would do the job for a few months before returning to work in a Boston hospital.Time – almost a half-century’s worth – proved her wrong.Lewin-Callahan retires Friday with a 45-year record of city service unsurpassed by any other currently employed city worker. Lewin-Callahan said Veterans Services employee Mary Cronin has her record beat by several months, but Lewin-Callahan’s 1969 start date is the oldest one listed in city Personnel Department records. “She’s one of the icons here – we’re going to miss her,” said Pauline Thomas, one of Lewin-Callahan’s Inspectional Services Department co-workers.Her colleagues, friends and family members will honor Lewin-Callahan during a coffee hour scheduled Friday in City Hall Room 302 between 9:30 and 11:30 a.m. They will not be saying goodbye to her: In addition to working as an ISD administrative aide, Lewin-Callahan also serves as Conservation Commission administrator and she plans to continue holding that part-time position, although she will no longer be working for the city.Former City Planner Kevin Geaney worked with Lewin-Callahan and said she never forgot a birthday.”She is the most thoughtful person you will ever come across. She’s one of those people who really care about how other people feel,” Geaney said.Lewin-Callahan said she is leaving city service with pride in the professional attention to detail she brought to her job.”I feel like a lot of people who call me know I know exactly what needs to be done,” she said.A Lynn Shore Drive resident, Lewin-Callahan said she is beating her husband, Philip Callahan, to the punch when it comes to retirement. He works in the construction industry and is on the verge of retiring. The couple will celebrate their 31st wedding anniversary in May.Lewin-Callahan graduated Classical High School in 1966 and attended the Chandler School for Women in Boston before going to work in the Boston Children’s Hospital seizure clinic. She loved the job but ended up taking a temporary position with the city, telling her mother, Rosita, she planned to quit city work and return to the hospital.”She said, ?Give it a year and see how you feel,'” Lewin-Callahan recalled.Her father, Carlos, and her mother were Cuban natives who left the island nation to join relatives in the United States and never returned. When she started working in City Hall, Lewin-Callahan handled secretarial duties for the Planning Department, working in Room 412.After she decided to remain in city employment, she continued working for city planners and worked for the DPW before joining Inspectional Services. She said every work day she has spent on City Hall’s top floor presented her with new questions about city codes and permit policies.”Every day is something different here,” she said. “It’s been two-thirds of my life.”