Velcro.js – Ajax bliss (Proof of concept)

Velcro can be considered an evolution of Chris Wanstrath’s PJAX.

Like PJAX, Velcro is used for seamlessly changing a part of a page instead of reloading and re-rendering a whole new page.

However, Velcro differs from PJAX on some fundamental aspects.

Principles

• The true benefit of Velcro is that CSS and JS assets aren’t reloaded nor re-executed. This greatly speeds up rendering.
• Transferring only the piece of content needed (without the layout) is considered micro-optimization. As long as only one HTTP request is made, transferring the extra bytes of your layout is less of a big deal than you might think.
• There is no reason for all this to require the use of history.pushState. In any AJAX context, including operations made in browsers not supporting history.pushState, Velcro can be of good help.

Benefits

• No server-side tweaks needed. Completely drop-in.
• Can update multiple parts of a page at a time.
• Doesn’t require the use of history.pushState.

Proof of concept setup

git clone git@github.com:rafBM/velcro-poc.git
cd velcro-poc
gem install sinatra sprockets coffee-script shotgun
shotgun