staff:

The most noticeable improvements:

• The new engine is scoped, so you’ll be able to nest and repeat blocks and variables.
• The engine uses a new token parser that will support special syntax for API hooks. This will let your theme call back for content, like:

  {​block:Posts type="photo" tagged="spotlight" count="5"}
      <img src="{​PhotoURL width="200"}" />
  {/block:Posts}

Umm…. whatever happened to this? This is not a thing.