rumqttc is a high level, easy to use client library that helps build applications which communicate over the MQTT protocol (commonly used in IoT devices). With this update we have been working towards making the client API a lot simpler and gradually improving/stabilizing v5 support.
It would certainly more work for you to maintain CLA for your project, but why does sqlite setup CLA? It is sufficiently big project and they could easily setup CLA if they wanted to.
On the same note, I recently shared a link[0] to his great beginner talk on functional programming languages. This was by far the best introduction to monoid, monads and few other functional programming terms.
Direct youtube[1] for those who don't want to click twice :)