Event handlers and application code are lazy-loaded and prefetched as needed. In a talk addressing How to Remove 99% of JavaScript From the Main Thread, Hevery introduced the rationale behind Qwik ...

One thing you might notice is the three <script> tags in the file. The first, in the head of the document, downloads dojo.js, the main Dojo source file, from the server. The second, also in the head ...