As said, the airport is small and (in my opinion) an absolute delight to travel through because of it. I have been through security, to the gate, sat down for a matter of 5 minutes and then walked straight onto the aircraft (just outside the doorway) that more or less immediately set off for the runway (a very short taxi stretch) and took off - and I was not holding up the flight. The whole thing from my going for the security check to takeoff was probably no more than 15 minutes, if that. Compare that with the bigger airports and the same can easily take in excess of an hour. But the advice already given is wise, do not rely on the absolute minimum of advance arrival to join the flight.