justintadlock
commented
8 years ago I'd actually recommend the same. No need for a large framework for something so small. Here's a tutorial I wrote. It's a little old, but it's still relevant: http://www.smashingmagazine.com/2011/10/create-custom-post-meta-boxes-wordpress/
Or, here's an example of some meta box code that I've worked on more recently: https://github.com/justintadlock/hybrid-core/blob/3.0/admin/meta-box-post-template.php
You have added cmb Meta Boxes just to add checkbox in page/post. If this is only what you need to do, consider adding it manually https://codex.wordpress.org/Function_Reference/add_meta_box rather than using a whole library.