Lowercased, shortened to 63 bytes, and with everything except 0-9 and a-z replaced with '-'. No leading or trailing '-'. Useful with URLs, host names, domain names, and stack names.

slugify.sh

#!/usr/bin/env bash
shopt -s extglob
# Lowercased, shortened to 63 bytes, and with everything except 0-9 and a-z replaced with '-'.
# No leading or trailing '-'. Useful with URLs, host names, domain names, and stack names.
slugify() {
  : "${1:?'Usage: slugify NAME'}"
  local next="$1"
  next="${next,,}" # lowercase
  next="${next//+([^a-z0-9])/-}" # replace non-alphanumeric wiht '-'
  next="${next#-}"    # remove - from the start
  next="${next%-}"    # remove - from the end
  next="${next:0:63}" # only first 64 char
  echo "$next"
}

[[ "${BASH_SOURCE[0]}" == "$0" ]] && "$@"