If you currently use bash, I wouldn't be much concerned that Python would be slow - in general, a general-purpose language would have more advanced interpreter

If you currently use bash, I wouldn't be much concerned that Python would be slow - in general, a general-purpose language would have more advanced interpreter than a shell. Python is also pretty high-level language with "batteries included", definitely more high-level than Go, Lua mentioned here. And with implementations like MicroPython (https://github.com/micropython/micropython https://github.com/micropython/micropython) you can be sure that you can scale down if needed (e.g. to a system with just 2-4MB of flash with Linux, or 128KB+ with bare-metal).