Binary package “libxcomposite-dev” in ubuntu cosmic

X11 Composite extension library (development headers)

 libXcomposite provides an X Window System client interface to the Composite
 extension to the X protocol.
 .
 The Composite extension allows clients called compositing managers to control
 the final drawing of the screen. Rendering is done into an off-screen buffer.
 .
 This package contains the development headers for the library found in
 libxcomposite1. Non-developers likely have little use for this package.
 .
 More information about X.Org can be found at:
 <URL:http://www.X.org>
 .
 This module can be found at
 git://anongit.freedesktop.org/git/xorg/lib/libXcomposite