This'll help you install Beyond Compare on your Gentoo, dawg.
This is a jargon which means installing software that official Gentoo repository is not providing. STFW to find out how to do it in two minutes.
Clone this repo and copy the folder dev-util to your local portage overlay.
emerge bcompare
Am I getting Beyond Compare for free?
Get your ass to the official website to buy a license. I ain't cracking anything.
I found a new version of Beyond Compare! I'm so hyped! What do I do?
Just change the filename according to the new version number. Then
ebuild <new ebuild filename> manifest
emerge -u bcompare