To bypass Sketch trial verification process you just need to spoof a couple of NSDate calls when the app starts. This repository contains a shared library code that can be inserted (using
DYLD_INSERT_LIBRARIES) to the Sketch process that spoofs the right
git clone https://github.com/gch1p/sketchtrial cd sketchtrial make
You can use
sketch.sh, it's a wrapper script that sets necessary environment variables to insert the lib and launches Sketch (it assumes that Sketch.app installed to /Applications, edit the script if it differs for you).
This hack doesn't work on systems with SIP (System Integrity Protection) enabled, and it's enabled by default since El Capitan. It can be easily disabled from Recovery Mode but it's another layer of security which is always good to have so disabling it permanently is not the wisest idea. I'll implement some solution to bypass this restriction when I have time.