js-loader.js

const Loader = {
  require (scripts, callback) {
    this.loadCount = 0;
    this.callback = callback;
    this.totalRequired  = scripts.length;
    scripts.forEach((src) => {
      this.writeScript(src)
    });
  },
  loaded (evt) {
    this.loadCount++;
    if (this.loadCount === this.totalRequired && typeof this.callback == 'function') {
      this.callback.call();
    }
  },
  writeScript (src) {
    const s = document.createElement('script');
    s.src = src;
    s.addEventListener('load', (e) => {
      this.loaded(e);
    }, false);
    document.querySelector('HEAD').appendChild(s);
  }
};

Loader.require([
    '{% static "admin/js/jquery.min.js" %}',
    '{% static "admin/js/jquery.init.js" %}',
], () => {
    console.log('ok, loaded jquery from admin');
})