Documentation / How it all works

How it all works

What happens when sitespeed.io analyzes a page (10 seconds version)

This is the super simple version, leaving out all other tools that are used:

  1. sitespeed.io gets a URL from the user
  2. Open the browser
  3. Start record a video of the screen
  4. Access the URL in the browser
  5. When the page is finished, take a screenshot of the page
  6. Run some JavaScripts to analyze the page
  7. Stop the video and close the browser
  8. Analyze the video to get metrics like FirstVisualChange and SpeedIndex
  9. Generate a HTML report and/or send the metrics to Graphite or store the metrics however you want, building your own plugin.

The big picture (with all the tools)

The big picture looks something like this:

How it all works

Built upon Open Source

Sitespeed.io uses a lot of other Open Source tools massive love to those projects:

The details

For the details you should read the developers guide.