That repo is dead, and the docs are outdated

Author: bjori

doc/tutorial.page

@@ -199,10 +199,6 @@ main (int   argc,
     </section>
 
     <section id="bcon">
-      <info>
-        <link type="guide" href="https://github.com/hanumantmk/BCON">BCON Project</link>
-      </info>
-
       <title>Using BCON</title>
       <p><em>BSON C Object Notation</em>, BCON for short, is an alternative way of constructing BSON documents in a manner closer to the intended format. It has less type-safety than BSON's append functions but results in less code.</p>