The present disclosure is generally directed to an on-board ROSA arrangement where a fiber receptacle element, optical components such as optical de-multiplexer (e.g., an arrayed waveguide grating (AWG)), turning mirror, photodiodes and light receiving chip are mounted to a common substrate. The fiber receptacle element includes a body that defines a slot to at least partially receive an end of the substrate and mount thereto. The body of the fiber receptacle further includes an aperture that extends through the body to receive an optical fiber and/or associated connector and align the same with ROSA components mounted on a surface of the substrate. The fiber receptacle body may be solid, e.g., formed from a single, monolithic piece of material, and may be manufactured from metal, plastic or other suitably rigid material.