The C64 itself wouldn't have enough memory (at least according to Wikipedia), but it seems like you could put Espruino on a ROM cartridge (I guess that's how you'd develop normally anyway).
Or if you just wanted the feel of it, you could connect something like an Espruino Pico up to the serial port on the back (I think you'd need an adaptor), and write a terminal application in C64 basic.
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, I think you probably could.
The C64 itself wouldn't have enough memory (at least according to Wikipedia), but it seems like you could put Espruino on a ROM cartridge (I guess that's how you'd develop normally anyway).
Or if you just wanted the feel of it, you could connect something like an Espruino Pico up to the serial port on the back (I think you'd need an adaptor), and write a terminal application in C64 basic.