macOS is a series of Unix oriented operating systems developed by Apple Inc.. macOS can also support other more portable user interfaces based on X11, to run applications that may look less Mac-like, but that are easier to port to other platforms. Huygens is only available in Mac as an X11 application, and therefore your need to have X11 installed on your Mac in order to run Huygens.


  1. We are exporting two versions for Mac OS: one for the Apple silicon CPUs (*M1.pkg) and one for Intel CPUs (*.x86_64.pkg). It is essential to download the version that corresponds to the CPU type of your Computer.
  2. It is required to use the XQuartz package to run Huygens as an X11 application. Please make sure you have the latest version for your OS version installed.
  3. If you encounter problems starting the Huygens Software after installing, select on your Mac: System Preferences → Security & Privacy → 'General' → click open anyway. A more general outline is given here: can I fix application thats not starting
  4. If you encounter problems to acces files or folders from Huygens on your Mac: System Preferences → Security & Privacy → 'Privacy' Tab → Full Disk access → add new → select your Huygens application.
  5. After OS upgrades, it sometimes is necessary to reinstall Xquartz or to restart the computer.

Still experiencing problems with Huygens? Please contact SVI.

macOS Big Sur 11, Monterey 12, Ventura 13

Installations on Big Sur, Monterey and Ventura are running fine, please follow the installation steps above. Huygens can be used on the Apple silicon CPUs using the correct Huygens installation package for Apple silicon based systems.

macOS Mojave 10.14 and Catalina 10.15

Installations on Mojave and Catalina are running fine, please follow the installation steps above. In rare cases Huygens will not start which is caused by an error in the permission settings (see above).

macOS Sierra 10.12 and High Sierra 10.13

If you have upgraded to Yosemite, El Capitan or Sierra from a previous Mac OS and had XQuartz previously installed, then the upgrade causes the symbolic link to the X11 directory to break. This is a known issue with the Mac OS upgrade. Because Huygens depends on X11 in Mac, Huygens will not be able to run at first.
The easiest solution is to first un-install XQuartz from your Mac and then re-install XQuartz.