The sequence of loading is as follows:
- The webpage loads and renders first.
- The Bolt scripts load after the webpage. This prevents script loading from delaying the page rendering.
- When prompted by the customer Bolt Checkout opens. Because the script has been pre-loaded, prior to checkout, the customer will not experience a delay due to script loading.
Some other points that are important to consider:
- Bolt uses industry standard caching procedures. This means that components will be cached on the browser for subsequent page visits. This prevents re-loading of scripts and components and thus avoids adding delays.
- The Initial script that triggers preloading, connect.js is small, about 100KB. The average for modern JS scripts is between 300KB - 400KB.
Below, see an example of script load times pulled from PageSpeed Insights. In the chart (ms) equals one millisecond. These times reflect script loads that are post webpage render, and pre-launch of Bolt Checkout.