Switch sub-chassis systems and methods for rack-scale servers are disclosed. A switch sub-chassis is arranged for modular installation in an enclosure and includes structural support features that allow multiple hot-serviceable line-cards and an integrated high-density optical fiber connectivity within the sub-chassis. Various features of the switch sub-chassis and associated line-cards allow liquid-electro-optical blindmate of the line-cards so that the line-cards are serviceable, allow high-density and complex fiber shuffle assemblies support, and facilitate ease of installation and/or servicing of fiber assemblies.