Is it safe to uninstall SIMBL agent on Yosemite?

I'm running the most resent version of Yosemite and have noticed something called SIMBL Agent in the login items setting. I've tried to remove it but when I do it my computer locks up and I can't get rid of it. I've done some research into and I'm just wondering if someone knows how to get rid of it. I've read that it's something to do with Apple developers.


The easiest way to uninstall SIMBL is to run the its bundled uninstaller. You can get a copy from the official website.

After the uninstallation check if these folders are present:

  • ~/Library/Application Support/SIMBL
  • /Library/Application Support/SIMBL

If they are present you can easily delete them.

Since OS X 10.11+ SIMBL gets broken due to the introduction of SIP by Apple (System Integrity Protection).

There is no need to disable SIP before the process and re-enable it later.