Devices and methods are provided for fluid delivery. The device may include a housing having an outer surface which includes a porous membrane, a fluid reservoir disposed in the interior region of the main housing and formed at least in part by a wall structure, a puncture mechanism operable to puncture the wall structure and form a fluidic path between the fluid reservoir and one or more channels in fluid communication with the porous membrane, and a positive displacement mechanism operable, following puncture of the wall structure, to drive a fluid out of the fluid reservoir, through the one or more channels, and into the porous membrane.
