We set out the following principles, to enable developers to make the most user friendly experience for editors and copywriters:
Email code is hard enough without your visual editor causing problems. Taxi doesnt change your structural code, or make any assumptions on email HTML. There are no extra requirements or restrictions on your HTML.
To make an Email Design System editable in Taxi you add extra tags and attributes (Taxi Syntax). As the designer you use the Taxi Syntax to design the editor's experience of the Design System.
Re-use content, use lean code and dont ask users to re-enter the same content.
Taxi uses a system of tags and attributes which don't show when an Email Design System is rendered. This means you can develop and test your HTML for rendering whilst they still contain Taxi Syntax If you load a Taxi Design System in a browser or send it as an HTML email the Taxi Syntax will not be visible.
All of the Taxi Syntax gets removed from the HTML when the email campaign is exported from Taxi, so there is nothing left except your Design System HTML and the content that has been put in.