A module for a gas sensor module is described herein. The module can include a first portion. The first portion of the module can include a first body and at least one first micro-resonator coupling feature disposed in and traversing the first body. The first body can be configured to be disposed within a cavity of a housing of the gas sensor. The at least one first micro-resonator coupling feature can be configured to align with at least one optical device of the gas sensor when the first body is disposed within the cavity of housing of the gas sensor. The at least one first micro-resonator coupling feature can be configured to have at least one first micro-resonator disposed therein.