noun-modifying (irregular), noun, noun or participle which takes 'suru', transitive verb
Describes something that is integrated into a system, device, or structure from the start, rather than added later. Used both as a prenominal modifier and as a noun with する for the act of building in.
このパソコンにはビルトインのカメラが付いている。
This computer has a built-in camera.
新しい機能をシステムにビルトインする予
We plan to build the new feature into the system.