Irish engineer!
Chief Miles O'Brien is a character in Star Trek: The Next Generation and Deep Space Nine. An Irish engineer, he spent the early seasons of TNG as a helmsman before becoming transporter chief. On Deep Space Nine he served as Chief Operations Officer and was responsible for the maintenance of the entire station. Afterwards he accepted a position teaching at Starfleet Academy, on Earth.
O'Brien is married to Keiko Ishikawa, and as of the end of DS9, they have a daughter, Molly, and a son, Kirayoshi. His best friend is Julian Bashir, with whom he is often paired in slashfic.