Linear luminaire

A linear luminaire, comprising:

• an elongate, three-sided enclosure with a top and a pair of depending sidewalls spaced apart by the top, the three-sided enclosure having a constant cross-sectional shape over its length, the top of the enclosure being translucent, the enclosure being open along an open side opposite the top;
• a rigid printed circuit board (PCB) with light-emitting diode (LED) light engines installed in a slot defined between the pair of depending sidewalls such that, when installed, the PCB closes at least a portion of the three-sided enclosure along the open fourth side, the PCB oriented such that light from the LED light engines is emitted from the top;
• engaging structure along respective inner faces of each of the pair of sidewalls below the slot in which the PCB is installed;
• and
• a mounting clip having engaging structure complementary to the engaging structure of the inner faces of each of the pair of sidewalls, the mounting clip, or a bracket engaged with the mounting clip, including
• an extension that, when the mounting clip is installed in the three-sided enclosure, extends along or parallel to a long axis of the three-sided enclosure, terminating proximate to an end of the three-sided enclosure,
• mounting structure at the end of the extension, and
• an endcap adapted to be received in and secured by the mounting structure to cover an end of the three-sided enclosure.