Apparatus and method for actively mitigating coherent errors by modifying an original quantum circuit, inserting Clifford gate operations at intermediate stages. Embodiments of the apparatus and method may perform CGI statically, at the compiling stage, and/or dynamically, at the control processing stage. The insertion of Clifford gates takes advantage of the symmetries in a quantum circuit and actively cancels coherent errors, maintaining the quantum processor in a state as close as possible to the original tune-up environment.