Lens-based optical connector assemblies and methods of fabricating the same are disclosed. In one embodiment, a lens-based connector assembly includes a glass-based optical substrate includes at least one optical element within the optical substrate, and at least one alignment feature positioned at an edge of the glass-based optical substrate, wherein the at least one alignment feature is located within 0.4 μm of a predetermined position with respect to the at least one optical element along an x-direction and a y-direction. The lens-based connector assembly further includes a connector element including a recess having an interior surface, The interior surface has at least one connector alignment feature. The glass-based optical substrate is disposed within the recess such that the at least one alignment feature of the glass-based optical substrate engages the at least one connector alignment feature.