but it does require a nRF51/52 DK/dongle for communication
Since you have an nRF52DK you could just use that?
@Gordon started
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Since you have an nRF52DK you could just use that?