From the introduction:
Svalbard has a unique take on the RPG scenario formula. The characters will enter Rooms, learn stuff, die, respawn, and then return to the same Rooms, but now armed with the knowledge that might keep them alive and help them progress through the scenario.
To keep things tense, to encourage good judgement, and to make smart choices, we use the concept of ‘finite’ time; that is, the scenario must be completed within a set period of time, or else Azathoth is unleashed upon the world, the characters die, and the players lose the scenario!
This finite time is called Time Units (TU). The characters have 8 TU to spend before time runs out and they lose. As they explore and learn and do things, time will pass, and a TU might be lost. Inevitably, the characters will die/respawn during the game, but upon their return, they might now have the knowledge how to reduce the amount of TU spent on one or more particular tasks.
Svalbard primarily is a scenario, intended to be compatible with any roleplaying system. However, the scenario also presents a very simple method of timed play that does not require any external system.