The Problem
When you suspend your computer, your LUKS key is saved in ram. Most users want their data to be encrypted when the lid is closed, not just when it's off.
Lots of scripts like c6fc's allow you to encrypt your data on lid close. Afaik, all of these solutions are distro-specific, or at least require systemD.
The solution here is based on creating a simple, self-contained, Alpine linux system in the /boot partition. When you suspend with the script provided, you'll be running off that one portable system.
Instructions
You must have an unencrypted /boot partition, which is generally the case.
Step 1:
Download the alpine archive and extract it to /boot/suspend
Step 2: Move the zzzluks to somewhere in your $PATH and make it executable.