Code blocks can be included and will be escaped correctly when using the back tick (```) for inline code (doc) or indenting the whole XML block with four spaces (doc). If you use HTML without indenting it or marking it as code with a back tick, it works just like regular HTML.

Example:

# Headline

    <b>This line isn't bold</b>
    <i>and this one is not italic</i>

<b>but *this one* is</b>

Will render to:

Headline

<b>This line isn't bold</b>
<i>and this one is not italic</i>

but this one is

from mdbl0g.