You can use npm to do this. In your package.json, add the following to the scripts key
...
"scripts": {
"build:jquery": "cp node_modules/jquery/dist/jquery.slim.min.js static/jquery/"
},
...
Then you can run: npm run build:jquery
You can add more build tasks to this section as you need them such as copying images and minifying scripts and css, then chain them together in a single command with npm-run-all:
$ npm install npm-run-all --save-dev
And...
...
"scripts": {
"build:jquery": "cp node_modules/jquery/dist/jquery.slim.min.js static/jquery/",
"build:images": "cp -R src/assets/images/ static/images/",
"build": "npm-run-all -p build:*"
},
...
Then run npm run build
npm is a great build tool and often bypasses the need for an additional build framework such as Gulp or Grunt. It can also handle file watchers and such to rebuild when things are modified automatically.