We released CCC 4.1.4 last week with a handful of minor bug fixes, as well as some enhancements and a stamp of approval for use with OS X 10.11 "El Capitan". This update is free for CCC 4 license holders, and recommended for anyone currently running CCC 4.
With the announcement of a ship date for El Capitan, perhaps you are counting down the days to when you can inflict it upon your production Mac. Or perhaps, like me, you're going to test it on your kid's Mac first and hope it doesn't wreck his Minecraft worlds. In either case, now is a great time to take another look at your backup hygiene. Many people don't realize this, but if you apply the "next major OS" upgrade to your Mac, Apple makes it darn near impossible to go back. The rub lies primarily within Apple applications such as Mail, Calendar, Address Book, etc. When you upgrade to the next OS, the data stores for these applications are upgraded as well, in a manner that is not backwards-compatible. So if you loaded El Capitan onto your system and realized that some major piece of productivity software doesn't work, getting back to Yosemite is not only challenging and time consuming, but you're also going to have a lot of trouble getting your email to work. That is, of course, unless you have a bootable backup of your pre-upgrade system.
Before you upgrade, make a bootable backup of your current system with Carbon Copy Cloner, detach the backup disk and set it on a shelf. Learn more about how to protect yourself from upgrade calamities here: Getting Ready for the El Capitan Upgrade
System Integrity Protection and Carbon Copy Cloner
El Capitan introduces a new feature called "System Integrity Protection" (SIP). A few people have asked us whether CCC "works" with SIP, and the short answer is, "Yes, absolutely". SIP doesn't have any implications for a bootable backup solution. Carbon Copy Cloner 4.1.4 is fully qualified with 10.11 El Capitan. Bootable backups created by CCC will preserve SIP, and SIP will be perfectly functional and happy on a cloned or restored system. To address the specific concerns raised by a few people, CCC can copy and set the "com.apple.rootless" extended attribute on system folders and files that are on the backup volume. I wouldn't be able to do that on the startup disk (SIP prevents that), but I'd never want to do that anyway; it would be foolish to make changes to the system files on the volume you're currently booted from.