Described are embodiments of apparatuses and systems of an active optical cable assembly including a connector plug configured to resist stress to optical fibers of the cable assembly. The connector plug may include a light engine mounted on a substrate, a jumper mounted on the substrate and configured to convey optical signals between an optical fiber and the light engine, and a fiber holder assembly configured to constrain motion of the optical fiber, the fiber holder assembly including a fiber holder on a first side of the substrate and a fiber holder cover on a second side of the substrate such that the optical fiber is fixedly held between the fiber holder and the fiber holder cover. Other embodiments may be described and/or claimed.