OpenDeck is an open-source desktop application designed for use with Elgato Stream Deck and similar devices.
It is compatible with plugins developed with the Elgato Stream Deck SDK and runs on every major desktop platform, including Linux.
Emergent (alpha)
Emergent is an open-source web-based versatile game engine.
It supports scripting with JavaScript, and thanks to its Git-based version control support, you can access your projects from anywhere.