@quasar/app/templates/app/ts/store/mutations.ts

Quasar Framework local CLI

import { MutationTree } from 'vuex';
import { ExampleStateInterface } from './state';

const mutation: MutationTree<ExampleStateInterface> = {
  someMutation (/* state: ExampleStateInterface */) {
    // your code
  }
};

export default mutation;