Barebones Angular 1 strong typed controller view model with TS

MyAppController.ts

module app {
    
    // Declare items explicitly the ng Controller will
    // expose to the template html
    export interface IMyViewModel {
        
        firstName: string;
        lastName: string;
        
        getFullname(): string;
    }
    
    class MyAppController implements IMyViewModel {
        
        firstName: string;
        lastName: string;
        
        getFullname = (): string => {
            
            return this.firstName + ' ' + this.lastName;
        }
    }
    
    angular
        .module('myapp')
        .controller('MyAppCtrl', MyAppController);
}