$ cat /etc/alpine-release 
3.7.0

$ ls
CODE_OF_CONDUCT.md  Dockerfile          README.md           install.sh          man                 test
CONTRIBUTING.md     LICENSE.md          bin                 libexec             package.json

$ sudo ./install.sh /usr/local/
readlink: unrecognized option: e
BusyBox v1.27.2 (2018-01-29 15:47:03 UTC) multi-call binary.

Usage: readlink [-fnv] FILE

Display the value of a symlink

        -f      Canonicalize by following all symlinks
        -n      Don't add newline
        -v      Verbose

$ ls -l $(which readlink)
lrwxrwxrwx    1 root     root            12 Feb 17 18:00 /usr/bin/readlink -> /bin/busybox