Surfaces to Finish:
    Win32 Surfaces — Microsoft Windows surface support
    Quartz Surfaces — Rendering to Quartz surfaces
    XLib Surfaces — X Window System rendering using XLib

Font backends to Finish:
    Quartz (CGFont) Fonts — Font support via CGFont on OS X
    User Fonts — Font support with font data provided by the user

Paths:
    Constructor and way to add data
    Iterator for path object

Other:
    API utilizing glyphs needs to be completed, a few functions in scaled font,
    backend fonts, and CairoContext

    Add ability to see values in matrix (read only properties, var_dump support) and
    in other objects as well

    clone handling

    Maybe implement cairo_svg_surface_create_for_stream and similar, allowing
    PHP callbacks/closures to be used as the callback
    Helper methods to convert image surfaces for use with imagick/gmagick/etc

1. Finish code completion (see above)

2. Tests written (good code coverage wanted)

3. Documentation