I'm using Node-RED for Hubitat<->rPi GPIO integrations. See https://nodered.org, and also A Node-Red Introduction for Hubitat Owners .
There is a really nice package of nodes that leverages the built-in Hubitat Maker-API endpoints, see Node-RED nodes for hubitat .
Node-RED has built-in nodes for rPi GPIO, so just about any integration can be implemented by constructing Node-RED flows, after adding these two packages to the Node-RED palette.
Here's a screenshot of my Node-RED palette, so you can see what I'm using for my integrations:
Hope this helps. Warning: Node-RED is intoxicating...
