How would I apply AND RUN fast-serve to an SPFx Teams Toolkit project

Question

I know how to install fast serve and have used it frequently in the past. But how would I configure a Teams Toolkit created SPFx webpart which I want to debug using fast-serve? Would I need to edit the gulp.js file? If so what with? Here's what the gulp file starts:

/src/node_modules/gulp/bin/gulp.js serve --nobrowser 

Build target: DEBUG
Using gulpfile D:\MyProject\src\gulpfile.js

and here's the gulp file:

'use strict';

const build = require('@microsoft/sp-build-web');

build.addSuppression(`Warning - [sass] The local CSS class 'ms-Grid' is not camelCase and will not be type-safe.`);

var getTasks = build.rig.getTasks;
build.rig.getTasks = function () {
  var result = getTasks.call(build.rig);

  result.set('serve', result.get('serve-deprecated'));

  return result;
};

build.initialize(require('gulp'));