conveying a gaseous hydrogen fuel (H2) and a gaseous hydrocarbon fuel (HC) into a cylinder in a gaseous fuel engine for combustion;

receiving an increased engine power output request;

boosting a power output of the gaseous fuel engine based on the increased engine power output request at least in part by varying a ratio of the H2 and the HC combusted in the cylinder; and

varying an in-cylinder combustion parameter based on the varying a ratio of the H2 and the HC; and

limiting perturbation to a performance profile of the gaseous fuel engine based on the varying an in-cylinder combustion parameter;

wherein boosting a power output of the gaseous fuel engine includes boosting the power output to a rated engine load level, and the limiting perturbation includes limiting a derate to the gaseous fuel engine.