There's also https://github.com/systemjs/systemjs https://github.com/systemjs/systemjs if you want more of a ponyfill approach. FWIW bundlers also don't use the

There's also https://github.com/systemjs/systemjs https://github.com/systemjs/systemjs if you want more of a ponyfill approach. FWIW bundlers also don't use the browser's functionality to load modules... It's a bit late to figure out, but I see caveats with dynamic imports in es-module-shims but not SystemJS.