HHVM provides dozens of built-in, integrated extensions and allows for other extensions to be dynamically loaded. Since this is an HHVM user's guide, this does not discuss how to build your own extension, but there are resources for that listed below.

Integrated Extensions

If you call get_loaded_extensions() from HHVM, you will find that the following extensions are integrated into HHVM

Dynamically Loaded Extensions


To load a dynamically loaded extension, follow the instructions for that extension. However, it generally goes like this:

cd /path/to/extension
cmake .

This will create an .so file. Then in your configuration .ini file:

extension_dir = /etc/hhvm
hhvm.extensions[extension_name] = extension.so


hhvm.dynamic_extensions[extension_name] = extension.so

Building Your Own Extension

Creating your own extension is beyond the scope of this user guide, but there are some good external resources to help get you started: