An illustrative shader construction system accesses a plurality of instructions based on a shader construction request. The plurality of instructions is associated with a shader component indicated in the shader construction request and includes a first instruction that relates to a selected platform indicated in the shader construction request and a second instruction that relates to a non-selected platform and that is incompatible with the selected platform. The shader construction system assembles a shader based on the plurality of instructions. The assembled shader is configured for use with the selected platform to perform a shader function implemented by the shader component. The shader construction system provides the assembled shader to a graphics rendering system configured to use the assembled shader to perform the shader function as part of rendering an image. Corresponding methods and systems are also disclosed.