Bionic support
The default pkl aarch64 executable doesn't work on termux (or Android, basically), and I have no idea how to recompile the source code. The only workaround as of now is using something like andronix, where the pkl executable does work.
What error do you see when you try to run pkl?
bash: ./pkl-linux-aarch64: cannot execute: required file not found
Basically, it's trying to get glibc files, which obviously doesn't work as android uses bionic instead.
Ah, gave it quick read (I hadn't ever looked at bionic). It seems it's very similar to musl, but not quite the same. For one, you should be using the Alpine builds (and you will likely need another build altogether, similar to the Alpine build)