Yes - RAK have been really interested in getting ports of Espruino for their devices, so there is some hope that there may be official support for that at some point :)
Really the only gotcha is adding support for LoRaWan on SX127x to Espruino. You could install Espruino on the RAK813 and send LoRa packets on the SX127x right now - it's just getting the relevant stuff to have it running on LoRaWan :)
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.
Yes - RAK have been really interested in getting ports of Espruino for their devices, so there is some hope that there may be official support for that at some point :)
Really the only gotcha is adding support for LoRaWan on SX127x to Espruino. You could install Espruino on the RAK813 and send LoRa packets on the SX127x right now - it's just getting the relevant stuff to have it running on LoRaWan :)