The Builders are a fictional alien race from the TV series Farscape.
They are the creators of the Leviathan biomechanical space-borne species, which is how they earned their name. They originally intended the Leviathans to be ordinary biomechanical ships, only later giving them souls and the ability to reproduce. The act of giving the vessels sentience has resulted in the Leviathans considering the Builders to be their gods.
It is unclear if the Builders are a species that has evolved to truly god-like levels as the full extent of their powers may not have been seen. Nor is it clear what their true appearance is, as they have demonstrated an ability to change their form at will. They have been seen to appear in a humanoid form, during which time they have pale skin and dress in Roman-esque clothing and can communicate with other humanoid lifeforms. They have also been seen to take a gaseous form, which allows them to travel through space and pass through solid matter.
They are introduced in Episode 2.11 "Look At The Princess: I Do, I Think", in which Pa'u Zotoh Zhaan must save Moya and Pilot by preventing a Builder from commanding Moya to sacrifice herself needlessly. The Builders were concerned that Moya was capable of giving birth to gunships such as Talyn, when Leviathans were supposed to be creatures of peace, and felt that the only way to prevent this from occurring again was for Moya to be decommissioned. Zhaan ultimately convinced the Builder to reconsider, after proving herself worthy of being Moya's protector.